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Silvia's Collection
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silvia




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PostPosted: Mar 19, 2022 16:05    Post subject: Huanzala Mine Report by Silvia  

REPORT MINERA SANTA LUISA
The Minera Santa Luisa (Huanzalá Mine) is a Zn/Pb/Cu/Ag deposit owned and operated by the Compañía Minera Santa Luisa S.A., which is a subsidiary of the Japanese company, Mitsui Mining and Smelting Ltd.

The first geological investigations in the area were carried out by Mitsui Mining and Smelting Company Limited a private Japanese company in 1961. In 1964 Compañía Minera Santa Luisa S.A., was created to exploit the deposit.

The Compañía Minera Santa Luisa has 3 economically active mining areas: SANTA LUISA (Huanzala), RECUERDO and PALLCA, the first two are within the Huanzalá Mining site. The Pallca mine lies some 50 km to the south of Huanzala.

LOCATION

The mine is located in the district of Huallanca, province of Bolognesi, department of Ancash. The closest town, Huallanca, is 12 Km by paved road, to the SE of the mine. The city of Lima is located some 412 km by road from the mine.

Geographically, the mine is located between the prolongation of the
Cordillera Blanca and Cordillera Huayhuash, south of Cerro Huanzalá and to the NE of a glacial valley through which the Torres River flows.

Its geographical coordinates (camp) are:

West Longitude: 76º 59' 50''
South Latitude: 09º 52' 04''

Its U.T.M. coordinates are:

East: 0280400.00
North: 8908650.00
ACCESSIBILITY

The access and route to Compañía Minera Santa Luisa is as follows:

• Lima – road detour to Huaraz (Pativilca) Paved 210 km
• Road detour to Huaraz - Paved Conococha 122 km
• Conococha – to Santa Luisa Paved 80 km

ORE BODIES

The silver-lead-zinc ore deposits of the Huanzala mine are bedded and massive orebodies replacing a limestone formation embedded in the Cretaceous sedimentary sequence. The orebodies are composed of three types of ore; pyritic ore, ore associated with an argillic alteration zone and skarn ore types. Pyrite mineralization controls the types and patterns of ore element distributions. High grade orebodies are adjacent to the pyrite bodies and consist mainly of the pyritic ore type.

ZONES

In the Huanzalá Mine, three distinct geological formations exist and they are called the Chimu Formation, the Santa Formation and the Carhuaz formation. These three formations are located on the inverted flank of an overturned syncline, in such a way that these formations overlap from the most recent to the oldest, later intruded by a Quartz Porphyry as an extrusive manifestation of a Granodiorite (Igneous) body dated to the Pleistocene.

The Quartz Porphyry seems to intrude the Chimú Formation in a Lacolith and in the Santa Formation it is present as a Dykes and Sills relatively parallel to bedding.


CHIMU

Chimu Formation, formed basically by metamorphic rocks, quartzites. It represents the lower horizons of the Lower Cretaceous, exhibits in the South West (Western flank) and North West (East flank) sectors of the black mountain range. Regionally, the Chimú region is made up of sandstone packages and grey white quartzites of fine and coarse grain and sub-rounded forms, with intercalations of shale, slate with thin stratigraphy and generally dark or black colors.

SANTA

Santa Formation, marine sequence composed of dark limestone with intercalations of black shales that overlie the chimú quartzites and underlies the Carhuaz formation. The Santa formation is composed in the lower part of a stratigraphic series of black to dark grey shales and Black clayey limestones, which pass towards the top to shales dark with intercalations of limonites and layers of limestone. The width of the formation is variable and the outcrops have a length between 100 m to 150 m.

In Huanzalá, the Santa Formation is made up of 2 members: The upper member of a thickness of 120m composed of limestone with shale intercalations and a lower member with a thickness of 40m, composed of sandstones, shales, calcarenites and thin layers of limestone.

CARHUAZ

Carhuaz Formation is made up of a thick sequence of reddish-brown sandy shale stratified in thin beds, contain limonite intercalations Reddish-brown in thick to medium layers in quartzite beds greyish brown with reddish tones due to weathering, in the lower ones occasionally appear thin layers with limestones fine grain black. The Carhuaz formation lies concordantly on the shales and limestones of the Santa formation, and underlies in accordance with the Farrat quartzites.
ORE DISTRIBUTION

The mine has a total of 20 levels from LEVEL Z which is the lowest at 3500 metres above sea level to LEVEL J which is the highest level at 4415 metres above sea level.

LEVEL ELEVATION LEVEL ELEVATION
J 4415 P 3950
I 4375 R 3890
H 4315 S 3850
G 4255 T 3800
F 4195 U 3750
E 4155 V 3700
D 4125 W 3650
C 4095 X 3600
B 4055 Y 3550
A 4015 Z 3500

MINERALIZED VEINS

The bulk of the Zn, Pb, Ag and Cu ore-body occurs in five (5) primary veins, with each developing into additional veins within the same vein structure. Veins 1, 2, 3 and 4 occur in the Santa Formation and Vein 5 occurs in the Carhuaz formation. The veins occur as stratiform and lenticular structures exceeding 300 metres in length with widths varying from 1 to 20 metres.

Vein 1 (V1)

This vein is near the contact with the Chimu formation. It has a length of 200 meters, with widths that vary between 1 and 15 meters. The vein contains areas of silicified limestone and bands of Pyrite. In some sections of the vein the mineralization is sub-divided into three veins designated as V1T, V1 PA AND V1 PB.

Vein 2 (V2)

This vein is located after the previous one, near a shale layer of 1-2 metres in thickness. It has been sub-divided into V2T, V2TB and V2P. It contains structures composed of shale and silicified limestone.

Vein 3 (V3)

Located below a brecciated horizon, it appears as a large area of mineralized ground, and it produces the best metal grades in the deposit. It has an average width of 15 metres. Consequently, this vein is one of greatest importance and the one that has been exploited with greatest emphasis. It is found near a 1.0 meter thick schist layer, and is subdivided into V3T, V3 and V3P.

Vein 4 (V4)

Located about 10 meters from V3, this vein is interspersed with layers of schist, pyrite or silicified limestone. The width of the vein varies from 1 to 8 metres. It is located near of two layers of schist, each about 0.4 metres thick.

Vein 5 (V4)

Located in the Carhuaz formation, about 8 meters from the contact with the Santa formation its width varies from 1 to 2 metres. The top of the vein is in contact with shale and silicified rock.

MAIN COMPONENTS OF THE MINE

The main facilities located within Mina Santa Luisa (Huanzalá Mine) area are:

• Camps and other buildings.
• Roads and entrances.
• Water, sewage and electricity services.
• Acid water treatment plant (PTAA).
• Installations related to the productive activity:
Concentrator plant,
Water intake works,
Offices
Maintenance workshops,
Analytical laboratory,
Warehouse and
Fuel tanks
• Waste disposal areas for tailings and for waste rock extracted from the mining during mineral exploitation.
• Laguna Contaycocha and related hydraulic structures.

MINING METHOD

For Huanzala the most practical and profitable mining method is ascending cut-and-fill stoping. The mineralized veins are extracted in horizontal slices beginning at the very bottom and advancing upwards towards the surface.

Ramps (inclined tunnels) are excavated to connect the surface to the underground ore body. Drifts are excavated to come in contact with the ore slices. The slices are drilled, blasted with explosives, and ore is removed by using dump trucks or other suitable vehicles.

The ore is then dumped into ore chutes, an inclined tunnel where ore is transported to a lower elevation in the mine. The ore is picked up at the other end of the ore pass by trucks. The ore is then transported out of the mine through a ramp to a processing plant at the surface.

Once a slice is completely mined out, the empty space is backfilled. The backfill material used can be a mixture of sand and rocks, waste rock with cement, or dewatered mill tailings. The backfill underground serves to keep the mine walls stable and becomes the floor for mining the next slice. Mining continues upwards towards the surface until the ore body is depleted.



01 local map.jpg
 Mineral: _
 Locality:
Huanzala Mine, Huallanca District, Dos de Mayo Province, Huánuco Department, Peru
 Description:
 Viewed:  11526 Time(s)

01 local map.jpg



02 - HUANAZAL MINE AERIAL VIEW.jpg
 Mineral: -
 Locality:
Huanzala Mine, Huallanca District, Dos de Mayo Province, Huánuco Department, Peru
 Description:
 Viewed:  11533 Time(s)

02 - HUANAZAL MINE AERIAL VIEW.jpg



03 - HUANAZALA.jpg
 Mineral: -
 Locality:
Huanzala Mine, Huallanca District, Dos de Mayo Province, Huánuco Department, Peru
 Description:
 Viewed:  11526 Time(s)

03 - HUANAZALA.jpg



04 - MAIN MINE PORTAL.jpg
 Mineral: -
 Description:
 Viewed:  11514 Time(s)

04 - MAIN MINE PORTAL.jpg



05 - MAIN GEOLOGICAL STRUCTURES.jpg
 Mineral: -
 Description:
 Viewed:  11509 Time(s)

05 - MAIN GEOLOGICAL STRUCTURES.jpg



06 - MINA HUANAZALA VEINS 3.jpg
 Mineral: -
 Description:
 Viewed:  11510 Time(s)

06 - MINA HUANAZALA VEINS 3.jpg



07 - CROSS SECTION.jpg
 Mineral: -
 Locality:
Huanzala Mine, Huallanca District, Dos de Mayo Province, Huánuco Department, Peru
 Description:
Main ore-bodies within the Mina Santa Luisa mine
 Viewed:  11526 Time(s)

07 - CROSS SECTION.jpg



08 ASCEND AND FILL FULL PROCESS.jpg
 Mineral: -
 Locality:
Huanzala Mine, Huallanca District, Dos de Mayo Province, Huánuco Department, Peru
 Description:
Mine exploitation method - ascend and fill.
 Viewed:  11501 Time(s)

08 ASCEND AND FILL FULL PROCESS.jpg



09 - MARKING OUT A NEW DRIVE.jpg
 Mineral: -
 Locality:
Huanzala Mine, Huallanca District, Dos de Mayo Province, Huánuco Department, Peru
 Description:
 Viewed:  11517 Time(s)

09 - MARKING OUT A NEW DRIVE.jpg



10 - DRILLING ROCK FACE.jpg
 Mineral: -
 Locality:
Huanzala Mine, Huallanca District, Dos de Mayo Province, Huánuco Department, Peru
 Description:
 Viewed:  11537 Time(s)

10 - DRILLING ROCK FACE.jpg



11 - HUANAZALA MINE DRIVE TO MAIN GALLERY.jpg
 Mineral: -
 Locality:
Huanzala Mine, Huallanca District, Dos de Mayo Province, Huánuco Department, Peru
 Description:
 Viewed:  11512 Time(s)

11 - HUANAZALA MINE DRIVE TO MAIN GALLERY.jpg



12 - HUANAZALA MINE MAIN ACCESS RAMP.jpg
 Mineral: -
 Locality:
Huanzala Mine, Huallanca District, Dos de Mayo Province, Huánuco Department, Peru
 Description:
 Viewed:  11526 Time(s)

12 - HUANAZALA MINE MAIN ACCESS RAMP.jpg



13 - LEVEL P.jpg
 Mineral: -
 Locality:
Huanzala Mine, Huallanca District, Dos de Mayo Province, Huánuco Department, Peru
 Description:
 Viewed:  11515 Time(s)

13 - LEVEL P.jpg



14 - HUANAZALA MINERALS.jpg
 Mineral: -
 Locality:
Huanzala Mine, Huallanca District, Dos de Mayo Province, Huánuco Department, Peru
 Description:
A happy miner showing his treasures. Quite good for common ore samples.
 Viewed:  11498 Time(s)

14  - HUANAZALA MINERALS.jpg



15 - TRUCK LOADED WITH ORE LEAVING MINE PORTAL.jpg
 Mineral: -
 Locality:
Huanzala Mine, Huallanca District, Dos de Mayo Province, Huánuco Department, Peru
 Description:
 Viewed:  11537 Time(s)

15 - TRUCK LOADED WITH ORE LEAVING MINE PORTAL.jpg


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silvia




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PostPosted: Mar 26, 2022 16:21    Post subject: Sulphur - Silvia's Collection  

Sulphur specimens from this mine are overlooked treasures in my opinion. We have a few large single Sulphur crystals from Bolivia in our collection, and we think they are just as fine as any Sulphur specimens from any other locality.


SULPHUR.jpg
 Mineral: Sulphur
 Locality:
El Desierto Mine, San Pablo de Napa, Daniel Campos Province, Potosí Department, Bolivia
 Dimensions: 8 cm x 5 cm x 4 cm
 Description:
A loose sparkling slightly translucent yellow crystal grouping of native Sulphur.
 Viewed:  11416 Time(s)

SULPHUR.jpg



LABEL.jpg
 Mineral: -
 Locality:
El Desierto Mine, San Pablo de Napa, Daniel Campos Province, Potosí Department, Bolivia
 Description:
Label
 Viewed:  11438 Time(s)

LABEL.jpg



EL DESIERTO BOLIVIA AERIAL PHOTO.jpg
 Mineral: -
 Locality:
El Desierto Mine, San Pablo de Napa, Daniel Campos Province, Potosí Department, Bolivia
 Description:
There are many Sulphur deposits in this region, but from the high resolution satellite images they seem to be abandoned. El Desierto has one intact structure with a fence. Behind the building and to the south there appears to be a drive/adit into the hill.
 Viewed:  11451 Time(s)

EL DESIERTO BOLIVIA AERIAL PHOTO.jpg



REGION ENCOMPASSING EL DESIERTO.jpg
 Mineral: -
 Locality:
El Desierto Mine, San Pablo de Napa, Daniel Campos Province, Potosí Department, Bolivia
 Description:
There are many Sulphur deposits in this region, but from the high resolution satellite images they seem to be abandoned. El Desierto has one intact structure with a fence. Behind the building and to the south there appears to be a drive/adit into the hill.
 Viewed:  11416 Time(s)

REGION ENCOMPASSING EL DESIERTO.jpg


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Don Lum




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PostPosted: Mar 26, 2022 17:18    Post subject: Re: Sulphur - Silvia's Collection  

silvia wrote:
Sulphur specimens from this mine are overlooked treasures in my opinion. We have a few large single Sulphur crystals from Bolivia in our collection, and we think they are just as fine as any Sulphur specimens from any other locality.


An excellent specimen and expert photography, Silvia.

Don

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Tobi
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PostPosted: Mar 27, 2022 12:59    Post subject: Re: Sulphur - Silvia's Collection  

silvia wrote:
Sulphur specimens from this mine are overlooked treasures in my opinion. We have a few large single Sulphur crystals from Bolivia in our collection, and we think they are just as fine as any Sulphur specimens from any other locality.
I think nothing can beat Sicily, but El Desierto is a good place for nice sulphur crystals. Thanks for your interesting post about the locality, again a very informative contribution.
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PostPosted: Mar 27, 2022 15:51    Post subject: Re: Silvia's Collection  

I do have a preference for the color of the sulphur from Desierto mine than from Sicily but the opposite preference for the shape. Thank you for your reportage, very interesting.

Have a nice week.
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silvia




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PostPosted: Mar 28, 2022 19:57    Post subject: Re: Silvia's Collection  

Dany Mabillard wrote:
I do have a preference for the color of the sulphur from Desierto mine than from Sicily but the opposite preference for the shape. Thank you for your reportage, very interesting.

Have a nice week.


Many thanks for your kind words.

The Sulphur specimens from Sicily differ from those from El Desierto by virtue of their geochemistry. El Desierto Sulphur specimens are true ‘volcanic’ specimens created in highly acidic environments. The matrix of El Desierto Sulphur specimens is highly altered by the action of Sulphuric acid - it is very porous and very soft. The bulk of the Sulphur specimens from Sicily were created in a sedimentary environment by different chemical processes. The Sicilian Sulphur specimens often exhibit accessory minerals such as Gypsum and Calcite that you would not see in any Sulphur specimen from El Desierto.

I should buy a few Sicilian Sulphur specimens but we are focusing on a suite of Romanian sulphides and sulphosalts.
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silvia




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PostPosted: Apr 02, 2022 15:56    Post subject: Malachite, Againv - Silvia's Collection  

Display view. Beautiful chatoyant green crystallized malachite.


01 - MINDINGI MALACHITE BOTRYOIDAL.jpg
 Mineral: Malachite
 Locality:
Mindingi Mine (Mindigi Mine), Swambo, Kambove District, Katanga Copper Crescent, Katanga (Shaba), Democratic Republic of the Congo (Zaire)
 Dimensions: 11 cm x 10 cm x 6 cm
 Description:
Malachite in all its forms is one of my favourite minerals.
 Viewed:  11137 Time(s)

01 - MINDINGI MALACHITE BOTRYOIDAL.jpg



02 - MINDINGI MALACHITE BOTRYOIDA.jpg
 Mineral: Malachite
 Locality:
Mindingi Mine (Mindigi Mine), Swambo, Kambove District, Katanga Copper Crescent, Katanga (Shaba), Democratic Republic of the Congo (Zaire)
 Dimensions: 11 cm x 10 cm x 6 cm
 Description:
Matrix view
 Viewed:  11155 Time(s)

02 - MINDINGI MALACHITE BOTRYOIDA.jpg


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silvia




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PostPosted: Apr 10, 2022 16:05    Post subject: Romanian Minerals - Silvia's Collection  

Lustrous and sharp Galena crystals to 40 mm with Siderite and Sphalerite.


01 - TURT GALENA.jpg
 Mineral: Galena, Siderite, Sphalerite
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Dimensions: 15 cm x 12 cm x 4 cm
 Description:
Display view
 Viewed:  11036 Time(s)

01 - TURT GALENA.jpg



02 - TURT GALENA.jpg
 Mineral: Galena, Siderite, Sphalerite
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Dimensions: 15 cm x 12 cm x 4 cm
 Description:
Matrix view
 Viewed:  11021 Time(s)

02 - TURT GALENA.jpg



03 - TURT GALENA.jpg
 Mineral: Galena, Siderite, Sphalerite
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Dimensions: 15 cm x 12 cm x 4 cm
 Description:
Detail of the crystals
 Viewed:  11034 Time(s)

03 - TURT GALENA.jpg



04 - TURT GALENA.jpg
 Mineral: Galena, Siderite, Sphalerite
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Dimensions: 15 cm x 12 cm x 4 cm
 Description:
Detail of the crystals
 Viewed:  11021 Time(s)

04 - TURT GALENA.jpg



05 - TURT GALENA.jpg
 Mineral: Galena, Siderite, Sphalerite
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Dimensions: 15 cm x 12 cm x 4 cm
 Description:
Detail of the crystals
 Viewed:  11008 Time(s)

05 - TURT GALENA.jpg



06 - TURT GALENA.jpg
 Mineral: Galena, Siderite, Sphalerite
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Dimensions: 15 cm x 12 cm x 4 cm
 Description:
Detail of the crystals
 Viewed:  11034 Time(s)

06 - TURT GALENA.jpg



MAP 2.jpg
 Mineral: -
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Description:
Locality photo showing Turt-Ghezuri mine and the nearby Turt-Penigher mine. Both abandoned and in ruins.
 Viewed:  11029 Time(s)

MAP 2.jpg


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Tobi
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PostPosted: Apr 11, 2022 01:35    Post subject: Re: Silvia's Collection  

Again a very showy and beautiful piece, Silvia. I love galena so it is actually not that hard to impress me with one, but that's an outstanding specimen. I love the size and the composition of the different minerals, the brown siderite gives a wonderful contrast to the sulfides. And on many of these specimens from Turt the siderite is just a coating of very small crystals, just like a brown crust. Your specimen shows well-defined siderite crystals that make it even more attractive.

Once again a great contribution, I love that specimen :-)

Best regards
Tobi
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silvia




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PostPosted: Apr 11, 2022 16:38    Post subject: Re: Silvia's Collection  

Tobi wrote:
Again a very showy and beautiful piece, Silvia. I love galena so it is actually not that hard to impress me with one, but that's an outstanding specimen. I love the size and the composition of the different minerals, the brown siderite gives a wonderful contrast to the sulfides. And on many of these specimens from Turt the siderite is just a coating of very small crystals, just like a brown crust. Your specimen shows well-defined siderite crystals that make it even more attractive.

Once again a great contribution, I love that specimen :-)

Best regards
Tobi


Hello Tobi:

I just love Romanian minerals – and Galena. In fact if you like ancient Volcanoes, and the low-sulphidation epithermal deposits they create, Romania is just about as good as they get. By looking at a Turt specimen, and noting the minerals present, it is very easy to determine where in the ore-body it was extracted.

The mineralogy of the Turt-Ghezuri Mine (Viezuri vein) system consists largely of Pyrite, Sphalerite, Galena, Chalcopyrite, Quartz and Carbonates, with subordinate sulphosalts, oxides and sulphates.

Galena prevails over Sphalerite in the upper part of the ore-body down to about -250m below sea-level. Below the -250m level the opposite occurs where Sphalerite prevails over Galena. Also in the lower part of the ore-body there is an increase in the occurrence of Copper mineralization in the form of Chalcopyrite. Gold occurred in the upper part of the ore-body but was mined out before 1900. So Turt produces a wonderful array of sulphide minerals in which one species dominates over another as you ascend or descend the ore-body.
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silvia




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PostPosted: Apr 17, 2022 16:34    Post subject: Silvia's Collection, from Romania  

The specimen comprises large lustrous twinned crystals of Chalcopyrite measuring to 5cm in size across the top of a crystallized Galena, Sphalerite and Pyrite matrix.


01 - TURT CHALCOPYRITE GALENA.jpg
 Mineral: Chalcopyrite, Galena, Sphalerite and Pyrite
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Dimensions: 14 cm x 11 cm x 5 cm
 Description:
Display view
 Viewed:  10751 Time(s)

01 - TURT CHALCOPYRITE GALENA.jpg



02 - TURT CHALCOPYRITE GALENA.jpg
 Mineral: Chalcopyrite, Galena, Sphalerite and Pyrite
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Dimensions: 14 cm x 11 cm x 5 cm
 Description:
Matrix view
 Viewed:  10743 Time(s)

02 - TURT CHALCOPYRITE GALENA.jpg



03 - TURT CHALCOPYRITE GALENA.jpg
 Mineral: Chalcopyrite, Galena, Sphalerite and Pyrite
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Dimensions: 14 cm x 11 cm x 5 cm
 Description:
Detail of crystals 1
 Viewed:  10743 Time(s)

03 - TURT CHALCOPYRITE GALENA.jpg



04 - TURT CHALCOPYRITE GALENA.jpg
 Mineral: Chalcopyrite, Galena, Sphalerite and Pyrite
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Dimensions: 14 cm x 11 cm x 5 cm
 Description:
Detail of crystals 2
 Viewed:  10736 Time(s)

04 - TURT CHALCOPYRITE GALENA.jpg



05 - TURT CHALCOPYRITE GALENA.jpg
 Mineral: Chalcopyrite, Galena, Sphalerite and Pyrite
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Dimensions: 14 cm x 11 cm x 5 cm
 Description:
Detail of crystals 3
 Viewed:  10750 Time(s)

05 - TURT CHALCOPYRITE GALENA.jpg



06 - TURT CHALCOPYRITE GALENA.jpg
 Mineral: Chalcopyrite, Galena, Sphalerite and Pyrite
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Dimensions: 14 cm x 11 cm x 5 cm
 Description:
Detail of the crystals 4.
 Viewed:  10742 Time(s)

06 - TURT CHALCOPYRITE GALENA.jpg


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silvia




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PostPosted: Apr 24, 2022 15:48    Post subject: Turt-GhezuriI Ore-Deposit - Silvia's Collection  

A brief overview of the Turt-Ghezuri ore-deposit

LOCATION

The Turt mine is located in the north-western part of the Neogene metal sub-province of the Eastern Carpathians in the Oas Mountains district, and close to the border with Hungary and Ukraine. The area is dominated by predominantly base-metal ore deposits with subordinate Mercury and Gold mineralization. The area contains three mines – Turt, Penigher and Socia. The most significant in the area in terms of size and mineralogy is the Ghezuri (Viezuri) – Turt ore deposit.

REGIONAL GEOLOGY

The Oas Mountains represent the north-western part of the volcanic chain of the inner part of the Romanian Carpathians. They consist of Neogene volcanic and sedimentary rocks located in the north-western part of the small Oas Basin, an eastern extreme of the Pannonian Basin. Epithermal lead and zinc ore formation was connected to the Neogene volcanic activity in the area. The metallogeny of the Oas Mountains is similar to the third stage mineralization in the Gutâi Mountains, and is predominantly base metal with subordinate mercury and gold mineralization. Based on dating using K-Ar and Ar-Ar methods, the metallogenic activity took place only in Pannonian (11.5–7.9 Ma) geologic era. The mineral deposits belong to mineralization formed in the subduction area of the inner Carpathian chain. The metal source was a calco-alkaline magma with high silica, alkali and volatile content. The mineralization is hosted by felsic rocks - dacites and porphyry microdiorites of subvolcanic character.

HISTORY

The Turt-Ghezuri mine began operation as a base metal producer in 1973. The only mining prior to that date was before 1900 when Gold was extracted from the upper part of the mineralized ore-body.

Systematic geological research and economic evaluation of the base-metal resource at Turt began after 1959. Exploratory mining, and systematic drilling programs, indicated the presence of significant reserves of Lead, Zinc and Copper with subordinate Gold and Silver.

From 20,000 tons in 1973, the amount of ore extracted reached 85,000 tons in 1975, respectively 250,000 tons per year in the years 1986-1989, at the same time the number of employees increased from 590 in 1986 to 1155 in 1996.

In the early years of the mine, ore was sent to the Baia Mare for processing. In 1991, construction of a flotation circuit began on the western slope of Ghezuri Hill. The plan was to process all mine products locally.

In 1999, as a result of technological problems at the mine, the nearby Turt Creek became seriously polluted with heavy metals. As the Turt Creek is a tributary of the Tur River, further operations at the Turt-Ghezuri Flotation plant were stopped by Government decree.

In 2007, the government then demanded the final closure of Turt Mine. The Turt Creek and the surrounding area were regularly monitored for heavy metal pollution for several years after the closure of the Turt-Ghezuri mine.

MIHAI ORE-BODY AND VIEZURI ORE-BODY

The main zone of mineralization at the Turt-Ghezuri mine is called the Viezuri vein. This vein is concentrated on the western part of a sub-volcanic microdiorite body that crosses sedimentary rocks belonging to the Pannonian (12-7 Mya) and Sarmatian (13-12 Mya) geologic time periods.

The upper part of the mineralization from the surface to a depth of about 300 metres is called the Mihai vein. This vein was mined prior to 1900 for Gold, leaving base metal mineralization in the footwall of the vein.

The Mihai vein and its veinlets lie in a wedge consisting of Pannonian sedimentary rocks between a subvolcanic porphyry microdiorite body and pyroxene hyalodacites. The main vein is accompanied by several branches.

Beneath the Mihai Vein, lies the main base-metal ore-body known as the Viezuri vein. The mineralization in this section of the deposit occurs as a series of vein beams in the subvolcanic body close to the western contact with the Pannonian sedimentary rocks. Exploratory drilling indicated that the mineralization had a vertical depth of at least 700 metres and a length of about 900 metres. The width of the mineralization varied from a few centremetre to tens of metres. The minerals of economic importance included Galena, Sphalerite and Chalcopyrite. The ore-body also contained Pyrite, Marcasite, Arsenopyrite, Sulphosalts and gangue minerals such as Fluorite, Siderite, Calcite, Baryte and clay minerals.

Two further mineralized areas designated as vein 270 and vein 320 were intercepted by exploratory drilling 90 meters and 160 meters respectively west to the previous ones on level -300m.

MINERALIZATION PHASES

The predominant mineralization in the mine exhibits several textural types - massive, banded, brecciated, and impregnated. Sometimes these are intermixed resulting in complex textures. Voids or geodes containing exceptional mineral crystals were also encountered.

The banded and brecciated textures often give an indication of the mineralization history. The bands are often a few millimeters wide, but can reach a width of centimeters, consisting of alternating layers of metallic minerals and gangue minerals. For example, interlayered quartz amethyst and base metal sulfides occur in some sections of the veins. The veins may also contain metal sulfides, quartz, and carbonates. Sometimes these veins reached an exceptional size of several metres.

The brecciated textures indicated the movements of mineralizing solutions during the history of deposition. In some sections of the ore-body they occurred at the interval separating different periods of deposition.

ZONATION

As a general observation it is noted that the lowest temperature of mineral deposition occurred in the upper zones and the highest temperatures of mineral deposition in the lower zones.

The general trend in the location of minerals of economic importance in these deposits is noteworthy - Gold in the upper levels where the temperature (ca. 100-1500C) of deposition was the lowest, lead-zinc in the middle levels of an intermediate temperature of deposition (ca. 150-2500C), and copper in the lower levels at the highest temperature (ca. 250-3000C). Even the largest veins exhibit polyascendant zonation in the polymetallic stage of mineral deposition. Sometimes the transition in the polymetallic stage from lead-zinc (+ some copper) to copper ore is gradual.

Dating studies indicated that the ore forming process in the Viezuri vein network preceded that which took place in other metallogenic zones in the Oas and Gutâii mountains.

ORE FORMING STAGES

Detailed geological work indicated that at the Turt-Ghezuri deposit, metallogenesis proceeded in four stages over a long period of time.

STAGE 1

During this phase feldspar (adularia) was deposited in the veins. This was followed by the deposition of Pyrite, Sphalerite, Hematite, Scheelite, Quartz and Chalcopyrite with Sphalerite exsolution and Chalcopyrite and Pyrrhotite with Cubanite inclusions.


STAGE 2

Under conditions of high sulphur fugacity and high temperatures, the second ore forming stage saw the deposition of Pyrite, Chalcopyrite, Sphalerite, Galena and Quartz. During this phase the deposition of Sphalerite prevailed over Galena.

STAGE 3

The third stage mineralization contained greater amounts of Galena in addition to Pyrite, Sphalerite, Chalcopyrite, Quartz and Clay minerals.

STAGE 4

Under conditions of low Sulphur fugacity and high CO2 activity, an assemblage made up of Carbonates (Siderite/Calcite), together with Pyrite, Sphalerite, Galena, Tetrahedrite, Bournonite, Jamesonite, Barite, and Marcasite formed.

SOME COLLECTOR QUALITY MINERALS FROM TURT

Calcite – Massive and euhedral crystals to 20 mm

Chalcopyrite – Massive, Scalenohedral, pseudotetrahedral crystals 1mm to 50 mm.

Quartz – compact bands and euhedral crystals to 30 mm

Dolomite – Rhombohedral crystals to 30 mm in geodes.

Galena – Compact bands associated with Pyrite and Sphalerite forming cubic, cube-octahedral, octahedral, rhombohedral–dodecahedral euhedral crystals to 50 mm in geodes.

Jamesonite – needle shaped crystals in Calcite, bordering Galena.

Pyrite – Cubic, cubic-pentagonal, pentagonal, octahedral euhedral crystals to 20 mm in geodes. Compact masses associated with Galena.

Sphalerite – Compact masses associated with Galena and Pyrite. In geodes, cubic, octahedral, dodecahedral, tetrahedral, cubo-octahedral crystals of Sphalerite to 20 mm. Iron content varies from 3 to 9 %.

Siderite – Compact bands of the third stage mineralization and as rhombohedral crystals to 10 mm. Sometimes Siderite has replaced other species, such as Calcite, forming casts of Siderite after Calcite.



01 - ROMANIAN MAP.jpg
 Mineral: _
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Description:
Locality map
 Viewed:  10561 Time(s)

01 - ROMANIAN MAP.jpg



02 - REGIONAL MAP.jpg
 Mineral: _
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Description:
Regional map
 Viewed:  10590 Time(s)

02 - REGIONAL MAP.jpg



03 - Cross-section through Tur¸t Ghezuri ore deposit.jpg
 Mineral: _
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Description:
Cross section
 Viewed:  10571 Time(s)

03  - Cross-section through Tur¸t Ghezuri ore deposit.jpg



04 - THE TURT MINE FROM ABOVE.jpg
 Mineral: -
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Description:
Years of neglect, vandalism, theft and planned demolition have left little for current and future mining archeologists to study. It is the doom of men that they forget!
 Viewed:  10551 Time(s)

04 - THE TURT MINE FROM ABOVE.jpg



05 - DERELICT FLOTATION PLANT WITH P1 SHAFT HEADFRAME IN BACKGROUND.jpg
 Mineral: -
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Description:
Before the headframe was demolished
 Viewed:  10567 Time(s)

05 - DERELICT FLOTATION PLANT WITH P1 SHAFT HEADFRAME IN BACKGROUND.jpg



06 -DERELICT FLOTATION PLANT P1 HEADFRAME REMOVED.jpg
 Mineral: -
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Description:
wide angle view, showing flotation plant and mine entrance to the left.
 Viewed:  10537 Time(s)

06 -DERELICT FLOTATION PLANT P1 HEADFRAME REMOVED.jpg



07 - FLOTATION PLANT.jpg
 Mineral: _
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Description:
Derelict Flotation plant - western side
 Viewed:  10548 Time(s)

07 - FLOTATION PLANT.jpg



08 - INSIDE FLOTATION PLANT.jpg
 Mineral: -
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Description:
Inside the flotation plant - just a skeleton of its former beauty.
 Viewed:  10552 Time(s)

08 - INSIDE FLOTATION PLANT.jpg



09 - ADIT LEVEL 320m.jpg
 Mineral: _
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Description:
Ghezuri Adit
 Viewed:  10547 Time(s)

09 - ADIT LEVEL 320m.jpg



10 - OLD PROCESSING FACILITY.jpg
 Mineral: -
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Description:
 Viewed:  10534 Time(s)

10 - OLD PROCESSING FACILITY.jpg



11 - OLD PROCESSING FACILITY.jpg
 Mineral: -
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Description:
 Viewed:  10561 Time(s)

11 - OLD PROCESSING FACILITY.jpg



12 - OLD PROCESSING FACILITY.jpg
 Mineral: -
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Description:
 Viewed:  10548 Time(s)

12 - OLD PROCESSING FACILITY.jpg



13 - OLD PROCESSING FACILITY.jpg
 Mineral: -
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Description:
 Viewed:  10545 Time(s)

13 - OLD PROCESSING FACILITY.jpg



14 - ORIGINAL ADIT TO MINA GHEZURI.jpg
 Mineral: -
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Description:
Old adit level
 Viewed:  10591 Time(s)

14 - ORIGINAL ADIT TO MINA GHEZURI.jpg



15 - RUSTING EQUIPMENT.jpg
 Mineral: -
 Locality:
Turt Mine, Turt, Negresti-Oas, Oas Mountains, Satu Mare, Romania
 Description:
Mining equipment left to rust
 Viewed:  10577 Time(s)

15 - RUSTING EQUIPMENT.jpg


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Michael Shaw
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PostPosted: Apr 25, 2022 08:37    Post subject: Re: Silvia's Collection  

Hi Silvia,

Thanks for posting these pictures of Turt. We have quite a few minerals from that locality in our collection and it's nice to see photos of the former operation.

Michael
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PostPosted: Apr 25, 2022 17:36    Post subject: Re: Silvia's Collection  

Michael Shaw wrote:
Hi Silvia,

Thanks for posting these pictures of Turt. We have quite a few minerals from that locality in our collection and it's nice to see photos of the former operation.

Michael


Hello Michael:

Many thanks. We are happy that our efforts are not in vain.

We also have many Romanian specimens from Turt, Herja and Cavnic-Boldut, and we aim to acquire more. We will also be posting similar mini reports on the Herja and Cavnic-Boldut mines too.

There are many reasons for collecting minerals, and we like to assemble collections that reflect the nature of the ore-body from which they were extracted.

Low-sulphidation epithermal ore bodies such as those that occur in the Oas and Gutai Mountains of Romania are fascinating beasts, and they are the source of some outstanding minerals – sulphides, sulphosalts and gangue. These ore-bodies show some common trends, gold and silver minerals in the upper part where temperature of deposition was the lowest, zinc and lead sulphides in the middle and copper minerals in the lowest portions where the temperature of deposition was the highest. Sometimes multiple mineralization stages over long periods of time create a fascinating array of mixed mineral species.
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PostPosted: Apr 29, 2022 17:21    Post subject: Boldut Mine- Silvia's Collection  

Striated, lustrous, jet-black twinned Sphalerite crystals, to 3 cm, fill a sculptural vugh in large matrix surrounded by spherical clusters of oxide-tinted Calcite rhombs.


01 - BOLDUT SPHALERITE.jpg
 Mineral: Sphalerite with Calcite
 Locality:
Boldut Mine, Cavnic mining area, Cavnic, Maramures, Romania
 Dimensions: 12 cm x 9 cm x 8 cm
 Description:
display view 1
 Viewed:  10299 Time(s)

01 - BOLDUT SPHALERITE.jpg



02 - BOLDUT SPHALERITE.jpg
 Mineral: Sphalerite with Calcite
 Locality:
Boldut Mine, Cavnic mining area, Cavnic, Maramures, Romania
 Dimensions: 12 cm x 9 cm x 8 cm
 Description:
display view 2
 Viewed:  10280 Time(s)

02 - BOLDUT SPHALERITE.jpg



03 - BOLDUT SPHALERITE.jpg
 Mineral: Sphalerite with Calcite
 Locality:
Boldut Mine, Cavnic mining area, Cavnic, Maramures, Romania
 Dimensions: 12 cm x 9 cm x 8 cm
 Description:
Matrix view
 Viewed:  10275 Time(s)

03 - BOLDUT SPHALERITE.jpg



04 - BOLDUT SPHALERITE CLOSE 1.jpg
 Mineral: Sphalerite with Calcite
 Locality:
Boldut Mine, Cavnic mining area, Cavnic, Maramures, Romania
 Dimensions: 12 cm x 9 cm x 8 cm
 Description:
Detail of the crystals
 Viewed:  10268 Time(s)

04 - BOLDUT SPHALERITE CLOSE 1.jpg



05 - BOLDUT SPHALERITE CLOSE 2.jpg
 Mineral: Sphalerite with Calcite
 Locality:
Boldut Mine, Cavnic mining area, Cavnic, Maramures, Romania
 Dimensions: 12 cm x 9 cm x 8 cm
 Description:
Detail of the crystals
 Viewed:  10287 Time(s)

05 - BOLDUT SPHALERITE CLOSE 2.jpg



06 - BOLDUT SPHALERITE CLOSE 3.jpg
 Mineral: Sphalerite with Calcite
 Locality:
Boldut Mine, Cavnic mining area, Cavnic, Maramures, Romania
 Dimensions: 12 cm x 9 cm x 8 cm
 Description:
Detail of the crystals
 Viewed:  10273 Time(s)

06 - BOLDUT SPHALERITE CLOSE 3.jpg



07 - BOLDUT SPHALERITE CLOSE 4.jpg
 Mineral: Sphalerite with Calcite
 Locality:
Boldut Mine, Cavnic mining area, Cavnic, Maramures, Romania
 Dimensions: 12 cm x 9 cm x 8 cm
 Description:
Detail of interface between crystals and matrix
 Viewed:  10273 Time(s)

07 - BOLDUT SPHALERITE CLOSE 4.jpg



LABEL.jpg
 Mineral: -
 Locality:
Boldut Mine, Cavnic mining area, Cavnic, Maramures, Romania
 Description:
label
 Viewed:  10281 Time(s)

LABEL.jpg


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Tobi
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PostPosted: May 02, 2022 01:53    Post subject: Re: Silvia's Collection  

Another very beautiful and showy Cavnic specimen, I like it!
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PostPosted: May 03, 2022 17:32    Post subject: Re: Silvia's Collection  

Tobi wrote:
Another very beautiful and showy Cavnic specimen, I like it!


Hello Tobi:

Many thanks for your kind words. I suspect that black minerals are not a favourite with many collectors. I see this in the pricing – the lower the iron content of Sphalerite, the greater the price. The ruby red gemmy variants can cost as much as rubies – lol.
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PostPosted: May 04, 2022 01:50    Post subject: Re: Silvia's Collection  

silvia wrote:
Tobi wrote:
Another very beautiful and showy Cavnic specimen, I like it!
Hello Tobi: Many thanks for your kind words. I suspect that black minerals are not a favourite with many collectors. I see this in the pricing – the lower the iron content of Sphalerite, the greater the price. The ruby red gemmy variants can cost as much as rubies – lol.
I know what you mean, Silvia, but I think it's somehow understandable. Sphalerite in general is a common mineral and even in good crystals it's not that rare. But the red & gemmy ones are something special and thus really expensive. I mean, it's a transparent gemmy sulfide - you don't find that often ;-) I have some translucent (not really gemmy) sphalerites (Germany, Bulgaria & Kazakhstan) in my collection and I really love them but I also like "ordinary" sulfides in grey or black, that's why galena is one of my favourite minerals ;-) Don't forget what I said some time ago in Michael Shaw's collection thread:
Tobi wrote:
silvia wrote:
I know many people have an aversion to black minerals, but some can be absolutely stunning [...]
Right, some collectors are only into colours and refuse black minerals, but there's also a huge fan base for black and grey, otherwise things like manganite, schorl, cassiterite, galena, stibnite, hematite or several rare silver ores (just to mention a few) would not have become so popular in the mineral collection world :-)
I think judging by the colour is not only stupid when it's about people but also when it's about minerals :-)

Best regards
Tobi
silvia wrote:
I suspect that black minerals are not a favourite with many collectors. I see this in the pricing [...]
I think people on the hunt for an old German manganite or a good Xuebaoding cassiterite won't agree ;-)
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PostPosted: May 04, 2022 02:45    Post subject: Re: Silvia's Collection  

A German Manganite was always on my 'must find a good one' list. I did eventually find one but then sold it when I narrowed the focus of my collection
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PostPosted: May 05, 2022 16:35    Post subject: Morocco - Silvia's Collection  

A ball of Marcasite on Quartz.


01 - MARCASITE 1.jpg
 Mineral: Marcasite, Quartz
 Locality:
Bou Nahas Mine, Oumjrane mining area, Alnif Commune, Tinghir Province, Drâa-Tafilalet Region, Morocco
 Dimensions: 140 mm x 90 mm x 80 mm
 Description:
Display view
 Viewed:  10018 Time(s)

01 - MARCASITE  1.jpg



02 - MARCASITE 2.jpg
 Mineral: Marcasite, Quartz
 Locality:
Bou Nahas Mine, Oumjrane mining area, Alnif Commune, Tinghir Province, Drâa-Tafilalet Region, Morocco
 Dimensions: 140 mm x 90 mm x 80 mm
 Description:
Matrix view
 Viewed:  10025 Time(s)

02 - MARCASITE  2.jpg



03 - MARCASITE CLOSE UP 1.jpg
 Mineral: Marcasite, Quartz
 Locality:
Bou Nahas Mine, Oumjrane mining area, Alnif Commune, Tinghir Province, Drâa-Tafilalet Region, Morocco
 Dimensions: 140 mm x 90 mm x 80 mm
 Description:
Detail of the crystals - Marcasite ball
 Viewed:  10041 Time(s)

03 - MARCASITE CLOSE UP 1.jpg



04 - MARCASITE CLOSE UP 2.jpg
 Mineral: Marcasite, Quartz
 Locality:
Bou Nahas Mine, Oumjrane mining area, Alnif Commune, Tinghir Province, Drâa-Tafilalet Region, Morocco
 Dimensions: 140 mm x 90 mm x 80 mm
 Description:
Detail of the crystals - matrix side
 Viewed:  10053 Time(s)

04  - MARCASITE CLOSE UP 2.jpg



04 - OUMEJRANE MINE aerial photo 2022.jpg
 Mineral: -
 Locality:
Bou Nahas Mine, Oumjrane mining area, Alnif Commune, Tinghir Province, Drâa-Tafilalet Region, Morocco
 Description:
OUMEJRANE MINE - MANAGEM

Located 90 km from the town of Zagora in southern Morocco, the Oumejrane copper mine has been operational since 2014. It is managed by Managem subsidiary CMO (Compagnie Minière d’Oumejrane) and produces Copper concentrate from 5 different worksites.
 Viewed:  10058 Time(s)

04 - OUMEJRANE MINE aerial photo 2022.jpg



05 - D'OUMERJANE 0.jpg
 Mineral: -
 Locality:
Bou Nahas Mine, Oumjrane mining area, Alnif Commune, Tinghir Province, Drâa-Tafilalet Region, Morocco
 Description:
Entrance to the underground mine.

We have some wonderful photos of this mine, both surface and underground thanks to Managem.
 Viewed:  10061 Time(s)

05 - D'OUMERJANE 0.jpg


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