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New finds out of Mexico - (10)
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Jean Sendero
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PostPosted: May 19, 2013 22:56    Post subject: New finds out of Mexico - (10)  

Mexico is always producing fine minerals and lately it has proven again to be true.

First from Mapimi, around 2 months ago, some incredibly yellow to orange colored mimetite have surfaced that can rival San Pedro Corralito for the color. These have an inverted tear drop shape. Individual drops can reach 2 cm according to what I have seen. I was told that only 7-8 flats of the yellow mimetite surfaced of which only 2 had some cabinet and larger miniature sized specimens that were damaged free. The remaining flats were made of miniature size specimens that had suffered a lot of damage. Other shapes are observed which can be popcorn kernels-like.... For those that were at the Houston show, you probably had the chance to see a few of these yellow mimetite very early on. But, I was told that they sold almost instantaneously.

Santa Eulalia has produced hemimorphite for ever. In recent months however, instead of the more common elongated white crystals, some thick flat blades forming rosettes have emerged. These can be clear to almost 5 cm (individual crystal) with some goethite inclusions and or hematitic inclusions giving them a reddish color. The luster is simply stunning.

Additionally, some fantastic smithsonite pseudomorphing calcite have made it to the surface. The best ones have scaleohedron to 5 cm and are yellow. Yes, yellow. Most of the material is on the brownish side but very few have the yellow color. Unfortunately, the fast majority have damaged points. Undamaged specimens are rare.

I am certain that these will be seen during the summer shows.

Cheers

Jean



IMG_8004.JPG
 Description:
Mimetite
Mina Ojuela, Mapimi, Durango, Mexico
8 x 7 x 3.5 cm
Plate of mimetite tear drops
 Viewed:  36261 Time(s)

IMG_8004.JPG



IMG_8026.JPG
 Description:
Mimetite
Mina Ojuela, Mapimi, Durango, Mexico
4 x 2 x 2 cm
Plate of bright yellow lustrous reversed tear drop like of mimetite crystal aggregates. Tear drops are up to 2 cm high
 Viewed:  36233 Time(s)

IMG_8026.JPG



IMG_8027.JPG
 Description:
Mimetite
Mina Ojuela, Mapimi, Durango, Mexico
4 x 2 x 2 cm
the other side
 Viewed:  36243 Time(s)

IMG_8027.JPG



IMG_8008.JPG
 Description:
Hemimorphite
Level 17, Mina El Potosi, Santa Eulalia, Chihuahua, Mexico
6.5 x 4 x 4.4 cm
Hemimorphite rosettes with crystals included by hematitic dust. Main crystal is 4 cm tall
 Viewed:  36254 Time(s)

IMG_8008.JPG



Smithsonite after calcite.JPG
 Description:
Smithsonite pseudo after calcite
Level 8th, Mina San Antonio, Sta Eulalia, Chihuahua, Mexico
7.5 x 6 x 4 cm
The yellowish version with unfortunately a small busted tip......There are better ones out there.
 Viewed:  36239 Time(s)

Smithsonite after calcite.JPG


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Tobi




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PostPosted: May 20, 2013 03:25    Post subject: Re: New finds out of Mexico - (10)  

Very interesting, Jean, thank you!
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PostPosted: May 20, 2013 04:28    Post subject: Re: New finds out of Mexico - (10)  

I have seen most of what Jean has mentioned here...although I still am looking for a mimetite as nice as his!

Jean is right that very few of the smithsonite pseudomorphs are undamaged and even fewer have great color like his...and the one below. Despite this three or four remain some of the best pseudos of this kind ever to emerge. They show successive replacement shells showing that the calcite was partially replaced, some was dissolved and the next layer was attacked. I have put several in acid and the internal structure shows that the smithsonite protrudes into the calcite...they are not simple epimorphs although they may have begun that way.

Apparently there is some production beginning from the top levels (8-9) of the Main Silicate Orebody in the Potosi Mine. This body is the.source of rhodochrosite and friends. The production stems from a Joint Venture between Grupo Mexico (owners of the Buena Tierra Mine and operators of the JV) and Minerales Nacionales de Mexico aka MINAMEX who own the Potosi Mine. This has reopened access to a lot of the upper level workings of the West Camp over the last 2 years, and we have already seen some benefits in the form of some large botryoidal smithsonites that came out in 2011 and 2012.

The hemimorphites that are coming out all come from the Oxide Zinc Orebody that extends from the 13th to the 17th Levels of the Potosi Mine. Some of the pieces have come out with brilliant black chalcophanite perched on the hemimorphite...and a few very nice willemites have also appeared.

On top of that are some nice and sharp triangular calcites from somewhere in the northern West Camp...probably the old Parcionera Mine (aka Goat Cave or Cueva de Chivas) another one of the major collctor access points for the West Camp.

Milpillas continues its decline. A few nice azurites have come out from under beds, but no decent material in any quantity has emerged. There have been a few oddly shaped malachite blobs...on and off matrix and a few large Barytes (to 5 cm) with a nice pale green-blue color. The cuprites that were available at Tucson time have disappeared.



2013 best hemi (8).JPG
 Description:
Hemimorphite
Oxide Zinc Orebody, Potosi Mine, Santa Eulalia, Chihuahua, Mexico
14 cm
Smithsonite ps calcite
8th level San Antonio Mine, Santa Eulalia, Chihuahua, Mexico
12 cm
best piece I have seen from the find
 Viewed:  36180 Time(s)

2013 best hemi (8).JPG



2013 good hemi (1).JPG
 Description:
Hemimorphite
Oxide Zinc Orebody, Potosi Mine, Santa Eulalia, Chihuahua, Mexico
12 cm
Red color is iron-oxide (hematite etc.) inclusions
 Viewed:  36143 Time(s)

2013 good hemi (1).JPG



2013 red hemi (2).JPG
 Description:
Hemimorphite
Oxide Zinc Orebody, Potosi Mine, Santa Eulalia, Chihuahua, Mexico
6cm
minature
 Viewed:  36159 Time(s)

2013 red hemi (2).JPG



2013 hemi and chalcophanite (3).JPG
 Description:
Chalcophanite on hemimorphite
Oxide Zinc Orebody, Potosi Mine, Santa Eulalia, Chihuahua, Mexico
10 cm
some of the chalcophanites are fragile hollow shells, some are solid
 Viewed:  36146 Time(s)

2013 hemi and chalcophanite (3).JPG



2013 SE calcite triangles (2).JPG
 Description:
Calcite
Parcionera (?) Mine, West Camp, Santa Eulalia, Chihuahua, Mexico
10 cm
distinctive sharp triangular crystals
 Viewed:  36153 Time(s)

2013 SE calcite triangles (2).JPG



2013 Milpillas malachite (7).JPG
 Description:
Malachite
Milpillas Mine, near Cuitaca, Municipio Santa Cruz, Sonora, Mexico
8 cm
typical of the recent finds
 Viewed:  36158 Time(s)

2013 Milpillas malachite (7).JPG



2013 willemite (4).JPG
 Description:
Willemite
Oxide Zinc Orebody, Potosi Mine, Santa Eulalia, Chihuahua, Mexico
8 cm
black in center is chalcophanite
 Viewed:  36159 Time(s)

2013 willemite (4).JPG



2013 Smithsonite ps (9).JPG
 Description:
Smithsonite ps calcite
8th level San Antonio Mine, Santa Eulalia, Chihuahua, Mexico
14 cm
best piece I have seen from the find
 Viewed:  36142 Time(s)

2013 Smithsonite ps (9).JPG



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PostPosted: May 20, 2013 05:25    Post subject: Re: New finds out of Mexico - (10)  

All Amazing specimens!!! Especially 2013 best hemi (8).JPG. Thank you Jean and Peter for showing.
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PostPosted: May 20, 2013 06:22    Post subject: Re: New finds out of Mexico - (10)  

Why do you affirm smithsonite is pseudomorph after calcite if both minerals have the same crystalline forms? (and both are on the same group).
Is some calcite remaining into the crystals? or is it smithsonite recrystallized (perimorph) on previous smithsonite crystals? or are they simply smithsonite crystals?
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PostPosted: May 20, 2013 06:37    Post subject: Re: New finds out of Mexico - (10)  

Hi
Thank you for sharing.
The crystalline texture may be favorable to pseudomorphosis, I think. Crystal size would be great for smithsonite.
Roger.
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PostPosted: May 20, 2013 11:02    Post subject: Re: New finds out of Mexico - (10)  

The Mexican minerals are largely represented / discussed in FMF as it is easy to notice using the feature Mexico in FMF Gallery or searching the word "Mexico" in the Forum's search: .

For this reason and considering our luck to have here Jean Sendero and Peter Megaw, two great experts of Mexican minerals as well as many other Mexican collectors, I believe that this thread has a potentiality that does deserve to be in the Featured Columns of FMF section with the hope that in the future it could be a kind of window to new finds of Mexico were them appear grouped.

So, I renamed, numbered, and moved this topic to the Featured Columns of FMF section. For more info about how the Featured Columns of FMF section works, please use this link
Jean Sendero the author of the first post in this thread and therefore creator of it is already mentioned in the THANK-YOUs in the correspondent reference thread
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PostPosted: May 20, 2013 18:07    Post subject: Re: New finds out of Mexico - (10)  

Carlos asks a good question about why I call these pseudomorphs. As he suggests, first and most obvious (although not from the pictures) is that many have cores of remnant calcite. Second is that identical coarse scalenohedral calcite is the most common late vug lining mineral throughout the primary sulfide ores throughout the San Antonio Mine. At depth these are typically white semi-transparent crystals, often studded with pyrite. At depth in the pockets that produce ludlamite and vivianite the scalenohedral calcites are replaced by coarse siderite. Third these pseudomorphs occur at the modern...and ancient...watertable where zinc flushed out of the overlying oxidized sulfide mineralization (sphalerite-galena-pyrrhotite) is redeposited as a supergene blanket. This area contains caverns lined with ropy and stalactitic smithsonite, pockets lined with large botryoidal blue smithsonite and coarse rice-grain smithsonite crystals. No unquestionable "primary" scalenohedral smithsonite occurs in this area. Within the pseudomorph zone the pseudos range from nearly solid replacements on completely oxidized sulfides, to semi-solid replacements on untarnished sulfides. Sometimes there is remnant calcite, sometimes they are shells. These combined observations indicate pretty conclusively that these are not primary smithsonite crystals.

But are they true replacement pseudomorphs? Looking at the interior of either the natural shells or specimens where remnant calcite is removed by acid shows that the insides of the shells are irregular with numerous protrusions, not smooth as one would expect from an epimorph from which the substrate crystal was later dissolved. Further, in some cases the interiors show fins and boxworks of smithsonite with rhombohedral patterns suggesting infiltration and replacement by Zn-rich fluids along cleavage planes. In the latest examples there are multiple scalenohedral shells suggesting repeated attack of calcite surfaces by repeated batches of Zn-rich fluids.

I think the data indicate that these formed as Zn-rich, acid fluids derived from meteoric waters infiltrating through Zn-Pb-Fe sulfide ores reached the paleo watertable and were neutralized by contact with the typical scalenohedral calcite that occurs throughout the mine. With neutralization, smithsonite was deposited, perhaps/probably (?) usurping the carbonate from the calcite and kicking out the Ca to solution.

There is a more detailed explanation of this...with more pictures and figures in the Mineral Monographs "Smithsonite" issue published in 2012.



Img13621.JPG
 Description:
smithsonite ps calcite
8th level San Antonio Mine, Santa Eulalia, Chihuahua, Mexico
4 cm
shell of smithsonite after calcite...
 Viewed:  35882 Time(s)

Img13621.JPG



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PostPosted: May 21, 2013 00:42    Post subject: Re: New finds out of Mexico - (10)  

Roger Warin wrote:
Crystal size would be great for smithsonite.

Thanks, Roger, it is not a bad arguing!
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PostPosted: Jun 14, 2013 04:27    Post subject: Re: New finds out of Mexico - (10)  

Peter Megaw wrote:
...But are they true replacement pseudomorphs? Looking at the interior of either the natural shells or specimens where remnant calcite is removed by acid shows that the insides of the shells are irregular with numerous protrusions, not smooth as one would expect from an epimorph from which the substrate crystal was later dissolved. Further, in some cases the interiors show fins and boxworks of smithsonite with rhombohedral patterns suggesting infiltration and replacement by Zn-rich fluids along cleavage planes. In the latest examples there are multiple scalenohedral shells suggesting repeated attack of calcite surfaces by repeated batches of Zn-rich fluids...

Just to confirm the Peter's description I add a copy of a recent analysis of the external part of this material to prove that this external part is true Smithsonite.



Smithsonite - 8th level_Mina San Antonio_Santa Eulalia_Chihuahua_Mexico.jpg
 Description:
 Viewed:  35265 Time(s)

Smithsonite - 8th level_Mina San Antonio_Santa Eulalia_Chihuahua_Mexico.jpg


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PostPosted: Aug 20, 2013 12:05    Post subject: Re: New finds out of Mexico - (10)  

The reddish Hemimorphite is pretty incredible!
Is it the real color, or is the picture a little different than the real one?
For several years I've been looking for a specimen, as was seen 5 years ago, of wulfenite in association with green mimetite from the Ojuela Mine.
Any news from this side? I was not able to buy a piece at that time, and now I still have some regrets as I can't find today a piece at a correct price...

In any case, a big thanks for sharing that with us!

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PostPosted: Aug 20, 2013 13:21    Post subject: Re: New finds out of Mexico - (10)  

Nico...the color is real

Yellow wulfenites on very yellow mimetite have come out of Ojuela recently. The best are VERY good...and very expensive.

There have also been more smithsonite pseudomorphs after calcite...but this time after bladed calcite instead of scahenohedral "dogtooth" crystals. The color is not as brilliant as the earlier ones, but the luster is very good. They also show a combination of epimorphic overgrowths and replacement pseudomorphing.

Bladed calcite is rare as "primary" calcite in the San Antonio Mine...most of the bladed calcite occurs in voids created during oxidation of the orebody, in contrast to the scalenohedral which is overwhelmingly associated with primary ore deposition. This just adds a nice fillip to the pseudomorphing story

Thanks to Ric for the shots



bladed ps 2 (4).JPG
 Description:
smithsonite ps calcite
8th Level San Antonio Mine Santa Eulalia Chihuahua Mexico
8 x 10 x 5 cm
 Viewed:  34205 Time(s)

bladed ps 2 (4).JPG



bladed ps 1 (8).JPG
 Description:
smithsonite ps calcite
8th level San Antonio Mine Santa Eulalia, Chihuahua, Mexico
10 x 10 x 5 cm
 Viewed:  34230 Time(s)

bladed ps 1 (8).JPG



bladed ps 1 (2).JPG
 Description:
smithsonite ps calcite
8th level Mina San Antonio Santa Eulalia Chihuahua Mexico
10 x 10 x 5
Backside of previous shot showing hollows where bladed calcite once resided...not irregular invasion of smithsonite into the voids
 Viewed:  34219 Time(s)

bladed ps 1 (2).JPG



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PostPosted: Aug 26, 2013 20:34    Post subject: Re: New finds out of Mexico - (10)  

Got a chance to look through some more of the new Ojuela mimetites (with and without wulfenite) at Arkenstone during last weekend's Dallas Symposium...and picked up a few small pieces. Thought you all would enjoy the pictures...and encouragement to participate next year...the DMCS is growing quickly and is a lot of fun (if you avoid late-night sessions with TP and his Polish vodka!)


Laurens mimetite web (2).jpg
 Description:
Mimetite
Mina Ojuela, Mapimi, Durango Mexico
5 x 3.5 x 3 cm
Nice miniature with great color and luster. Lauren Megaw specimen
 Viewed:  33994 Time(s)

Laurens mimetite web (2).jpg



mimetite with wulfenite (2).JPG
 Description:
mimetite with wulfenite
Mina Ojuela, Mapimi, Durango Mexico
5 x 5 x 3 cm
Another colorful piece with wulfenite "ear"
 Viewed:  33981 Time(s)

mimetite with wulfenite (2).JPG



mimetite with wulfenite (1).JPG
 Description:
wulfenite on mimetite
Mina Ojuela, Mapimi, Durango Mexico
.7 x .7 cm
close up of the wulfenite ear
 Viewed:  33985 Time(s)

mimetite with wulfenite (1).JPG



Peters mimetite web.jpg
 Description:
mimetite
Mina Ojuela, Mapimi, Durango Mexico
8 x 6 x 4 cm
Small cabinet piece with great color
 Viewed:  33979 Time(s)

Peters mimetite web.jpg



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PostPosted: Jan 05, 2014 06:58    Post subject: Re: New finds out of Mexico - (10)  

The classic localities, Mapimi, Santa Eulalia, Naica etc….all in the northern part of Mexico are producing specimens in quantity these days. A recent post by P Megaw on December 17 clearly shows this with the re-occurrence of the rhodocrosite from Santa Eulalia.

New localities are not commonly spoken of and even less common, new localities in the southern part of Mexico. A region that I am particularly interested in as it forms one of my main sub collecting interest of my Mexico collection.

This past October (Pacific NW chapter of the Friends of Mineralogy) and November (New Mexico Mineral Symposium), we have seen surfacing some new amethyst from these part of the country. The amethyst is not from the famous Amatitlan area or Las Vigas or Taxco but, it was originally thought to be from Zacualpan, in the state of Mexico north of Taxco. This is a small village where a few small silver mines are operating on a very small scale. The original pieces that made it to the market were few and rapidly found new homes in someone collection.

The amethyst form elegant groups with crystals that can reach 7 cm in length. They have a very dark purple core with the outer part of the crystals has a lighter color. The material shows good “gemminess”. The luster is moderate on most however some have great luster.

Since, XTAL – Dennis Beals Minerals, has been very busy acquiring more of these and has successfully done so. I have seen a variety of specimens ranging in sizes from miniature to simply giants. In the process of acquiring the lots from 3 different individuals, Dennis found out that the original locality thought to be Zacualpan was erroneous. It turns out to be in Guerrero but more than 75 km further to the east than the original locality.

This is a very exciting new find, a new locality in southern Mexico. I believe Dennis will have those out in Tucson with a serious new collection of tequila to sample.



Amethyst Guerrero Original group.jpg
 Description:
Quartz var. Amethyst
Undisclosed - Guerrero - Mexico
Various sizes
Original mini lot of the amethyst presented at the Friends of Mineralogy Symposium NW Pacific Chapter. The circled specimen is featured below
 Viewed:  31510 Time(s)

Amethyst Guerrero Original group.jpg



Amethyst Guerrero Original.jpg
 Description:
Quartz var. Amethyst
Undisclosed - Guerrero - Mexico
7.5 x 6.2 x 4.5 cm
Original lot
 Viewed:  31456 Time(s)

Amethyst Guerrero Original.jpg



Amethyst Guerrero Large one.JPG
 Description:
Quartz var. Amethyst
Undisclosed - Guerrero - Mexico
30 x 25 cm approx
A smoker giant piece. Note the 15 cm ruler at the base of the specimen.
 Viewed:  31460 Time(s)

Amethyst Guerrero Large one.JPG


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PostPosted: Jan 05, 2014 08:58    Post subject: Re: New finds out of Mexico - (10)  

Wonderful specimens, thank you for sharing!
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PostPosted: Jan 22, 2014 15:09    Post subject: Re: New finds out of Mexico - (10)  

[quote="Tobi"]Wonderful specimens, thank you for sharin


Really nice . The next Tucson 2014 will be more clear the future of this new locality, still its not clear the ubication, Morelos, or Guerrero, or Mexico States. Any way, this locality have one more feature: green and complex habit of quartz.



1519057_249847898509429_1730453801_o.jpg
 Description:
Amethyst with some green mineral inclusions
South of México.
12x10x6 cm
Saludos
 Viewed:  31058 Time(s)

1519057_249847898509429_1730453801_o.jpg


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PostPosted: Jan 22, 2014 19:42    Post subject: Re: New finds out of Mexico - (10)  

Now here is a green quartz spécimen associated with amethyst, amethyst crystal has a phantom green color also.
I said that the future of this locality we will see in tucson 2014 because some dealers will if arouses interest this localities there will be more demand for specimenes and have more people looking for the actual locality and may contact the miners to help them to dig and retain the best crystals . If in the state of Morelos no mining experience, if Guerrero also the mining experience is low and if in the state of Mexico, near the mining district Zacualpan only security issues we will have to take into account to contact miners directly



IMG_0082.JPG
 Description:
Close up ,Amethyst with Greeen Quartz
South of México
7x4x5 cm specimen
The size of amethyst crystal is 2cm tall
 Viewed:  30982 Time(s)

IMG_0082.JPG


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PostPosted: Jul 14, 2014 12:16    Post subject: Re: New finds out of Mexico - (10)  

Now we have a new locality for Amethyst in México, Tejupilco.


10462995_303971283097090_1004353701880673737_n.jpg
 Description:
Amethyst
Tejupilco, México.
12x7x3cm
Color and luster are superior to Amatitlán.
 Viewed:  28331 Time(s)

10462995_303971283097090_1004353701880673737_n.jpg



10492063_303971483097070_9022557017135151049_n.jpg
 Description:
Amethyst
Tejupilco, México.
7x4x2.5cm
 Viewed:  28368 Time(s)

10492063_303971483097070_9022557017135151049_n.jpg


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Jean Sendero
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PostPosted: Jul 19, 2015 15:09    Post subject: Calcite from Palmarejo, Chinipas, Chihuahua, Mexico  

At the Tucson show 2015, we started to see some regular looking calcite reported to be from the Palmarejo mine in the state of Chihuahua. The two dealers that had some were asking an arm and a leg for some chipped scalenohedra, of grayish color and opaque. I ended up never acquiring one. Nevertheless, I had never heard of the mine so I did a little bit of investigating on the internet. Those findings are summarized below but in the course of doing this, I started to find and acquire several new calcite specimens which I believe, can compete with any great Mexican calcite locality by the diversity of crystal forms, the clarity of some crystals, the presence of spectacular inclusions and fantastic fluorescence. Color diversity is missing but compensated by transparency.

The mine is owned and operated by Coeur Mexicana and located on the western flank of the Sierra Madre Occidental, 270 km to the southwest of Chihuahua as the crow fly. The units forming the Sierra, poorly deformed and relatively flat-lying sequence of Tertiary-aged volcanic and sedimentary rocks, are cut by numerous intrusive rocks. The Sierra Madre hosts several ore deposits and the Palmarejo Mine is one of them.

The Palmarejo mine is harvesting Au and Ag from a complex system of veins, breccias and stockwork. It is classified as an epithermal low sulphidation system. The vein system trend generally northwest to southeast and dip either southwest or northeast. The dip on the structures ranges from about 45 to 70 degrees. In the mineralized portions of the structures, gold and silver are zoned from top to bottom with higher silver values occurring in the upper parts and higher gold values in the lower parts, sometimes accompanied by base metal mineralization, though variations are common.

The veins systems have a diversified mineralogy according the 43-101 metallurgy section which mentions 19 species of native elements and minerals or series hosting the Au and Ag. These are in no special order, electrum, native gold, native silver, jalpaite, aguilarite, pyrite, sphalerite, galena, chalcopyrite, altaite, billingsleyite, cervellite, tennantite-tetrahedrite, proustite, pearcite-polybasite, covellite-digenite, mckinstrite and stromeyerite. To date, and to my surprise, none of these have been reported, to my knowledge, as “quality collection specimen”.

The Palmarejo property contains a number of mineralized zones, the most important of these being the Palmarejo area where 5 zones or "clavos," are being exploited. La Prieta and La Blanca zones are exploited by open pit while the other three zones by underground mining. The open pit is exploited as usual with drill and blast, truck and shovel operations. The underground workings are accessed via three separate portals. The mine produce from all mining areas approximately 6,000 tonnes of ore per day. The ore is crushed, milled, and floated which results the recovery of silver and gold forming a doré shipped to Coeur’s smelting and refining partners in the U.S. and Europe.

Back to the calcite, the photos below are telling the story, for now. At least two generations of calcite are present, the latest one growing on top of the first one in in what seems to be on occasion, continuous without a real break other than the transitional deposition of what has been called Mn and Fe oxides.

The first episode of crystallization appears to be preferentially forming scalenohedron. Some nice twinned crystals and even some big fish tail looking ones, are present. This early phase of crystallization produces super clear to grayish to brownish colored scalenohedron crystals. Inclusions of reported Mn oxides are common and can have a beautiful arborescent form in the core of the crystal.

The second phase of crystallization covers the original scalenohedra crystals and produce some modified scalenohedra generally of clear nature to foggy. The second generation growth can partially or fully embed the first generation crystals. On occasion it is possible to observe a vertical growth on top of the pre-existing crystal suggesting continuity in the crystallization following a short hiatus that allowed the deposition of the Fe or Mn oxides.

The two generations of calcite are further defined by their distinctive fluorescence. The first generation under short wave is a spectacular bright orangey red, or with lesser intensity under medium or long wave exposition. The second generation does not fluoresce making for a bright core surrounded by non-fluorescent material.

The photos below show the diversity in crystal forms, examples of the two generations, the inclusions and the fluorescence. I hope you will agree with me that these are starting to stand out compared to the original find in late 2014. Note size of the crystals on some of the specimens, up to 15 cm.

It would be interesting to know from which workings these are coming from. If anyone knows, I would appreciate additional precision on the provenance.

The fluorescence of the calcite is likely due to the presence of Mn in the fluids, so why would the inclusions be Mn oxides if the system was oversaturated in Mn. Should we be expecting one of these days to see some rhodocrosite coming from Palmarejo?

Could some of the inclusions be something a little more exciting (i.e. sulfosalts instead of Fe or Mn oxides)? In the paragenetic sequence of these deposit type, it is not uncommon to have the sulphides and sulfosalts precipitated in between calcite and quartz stages.

Cheers

Jean

p.s. I Photoshopped some of the backgrounds to provide homogeneity. The minerals are untouched. Thank you to Moninaz123, Ricblair369 and Southershrike, all eBay vendors.



000 - Calcite Palmarejo Chinipas Chihuahua.jpg
 Mineral: Calcite
 Locality:
Palmarejo Mine, Palmarejo, Municipio Chinipas, Chihuahua, Mexico
 Dimensions: app 8 cm across
 Description:
From Tucson 2015.
 Viewed:  23505 Time(s)

000 - Calcite Palmarejo Chinipas Chihuahua.jpg



001 - Calcite Palmarejo Chinipas Chihuahua.jpg
 Mineral: Calcite
 Locality:
Palmarejo Mine, Palmarejo, Municipio Chinipas, Chihuahua, Mexico
 Dimensions: 7.6 x 10 x 5.4 cm
 Description:
Scalenohedra with a clear demarcation in the center where the inclusions stop and the crystal kept on growing.
 Viewed:  23595 Time(s)

001 - Calcite Palmarejo Chinipas Chihuahua.jpg



002 - Calcite Palmarejo Chinipas Chihuahua.jpg
 Mineral: Calcite
 Locality:
Palmarejo Mine, Palmarejo, Municipio Chinipas, Chihuahua, Mexico
 Dimensions: app 8 x 8 x 7 cm
 Description:
Modified scalenohedra forming an esthetic “rose” exhibiting likely the first generation with Mn spots on the outside of the crystals.
 Viewed:  23562 Time(s)

002 - Calcite Palmarejo Chinipas Chihuahua.jpg



003 - Calcite Palmarejo Chinipas Chihuahua.jpg
 Mineral: Calcite
 Locality:
Palmarejo Mine, Palmarejo, Municipio Chinipas, Chihuahua, Mexico
 Dimensions: 7.5 x 6.3 x 5.7 cm
 Description:
Twin crystal with both generations of calcite. The second generation appears to solely grow on the top of the crystal.
 Viewed:  23602 Time(s)

003 - Calcite Palmarejo Chinipas Chihuahua.jpg



005 - Calcite Palmarejo Chinipas Chihuahua.jpg
 Mineral: Calcite
 Locality:
Palmarejo Mine, Palmarejo, Municipio Chinipas, Chihuahua, Mexico
 Dimensions: 7.5 x 6.3 x 5.7 cm
 Description:
Side view. Twin crystal with both generations of calcite. The second generation appears to solely grow on the top of the crystal.
 Viewed:  23475 Time(s)

005 - Calcite Palmarejo Chinipas Chihuahua.jpg



006 - Calcite Palmarejo Chinipas Chihuahua.jpg
 Mineral: Calcite
 Locality:
Palmarejo Mine, Palmarejo, Municipio Chinipas, Chihuahua, Mexico
 Dimensions: app 8 x 6 x 4 cm
 Description:
Super clear scalenohedra with arborescent style Mn oxides inclusions.
 Viewed:  23506 Time(s)

006 - Calcite Palmarejo Chinipas Chihuahua.jpg



007 - Calcite Palmarejo Chinipas Chihuahua.jpg
 Mineral: Calcite
 Locality:
Palmarejo Mine, Palmarejo, Municipio Chinipas, Chihuahua, Mexico
 Dimensions: app 8 x 6 x 4 cm
 Description:
Close up viewSuper clear scalenohedra with arborescent style Mn oxides inclusions.
 Viewed:  23503 Time(s)

007 - Calcite Palmarejo Chinipas Chihuahua.jpg



008 - Calcite Palmarejo Chinipas Chihuahua.jpg
 Mineral: Calcite
 Locality:
Palmarejo Mine, Palmarejo, Municipio Chinipas, Chihuahua, Mexico
 Dimensions: app 8 x 12 x 10 cm
 Description:
Very esthetic group of scalenohedra
 Viewed:  23547 Time(s)

008 - Calcite Palmarejo Chinipas Chihuahua.jpg



009 - Calcite Palmarejo Chinipas Chihuahua.jpg
 Mineral: Calcite
 Locality:
Palmarejo Mine, Palmarejo, Municipio Chinipas, Chihuahua, Mexico
 Dimensions: app 9.5 x 12.5 x 8.5 cm
 Description:
Clear modified scalenohedra with Mn inclusions clearly visible.
 Viewed:  23572 Time(s)

009 - Calcite Palmarejo Chinipas Chihuahua.jpg



011ps - Calcite Palmarejo Chinipas Chihuahua.jpg
 Mineral: Calcite
 Locality:
Palmarejo Mine, Palmarejo, Municipio Chinipas, Chihuahua, Mexico
 Dimensions: app 7 cm across
 Description:
Example of second generation partially coating the first generation scalenohedron. (view is app. 7 cm across)
 Viewed:  23507 Time(s)

011ps - Calcite Palmarejo Chinipas Chihuahua.jpg



012ps - Calcite Palmarejo Chinipas Chihuahua.jpg
 Mineral: Calcite
 Locality:
Palmarejo Mine, Palmarejo, Municipio Chinipas, Chihuahua, Mexico
 Dimensions: app 27 x 15 x 15 cm
 Description:
Another example of second generation partially coating the first generation scalenohedron. (Largest crystal is 15 cm the piece is 27 cm across)
 Viewed:  23616 Time(s)

012ps - Calcite Palmarejo Chinipas Chihuahua.jpg



013 - Calcite Palmarejo Chinipas Chihuahua.jpg
 Mineral: Calcite
 Locality:
Palmarejo Mine, Palmarejo, Municipio Chinipas, Chihuahua, Mexico
 Dimensions: app 10 x 15 x 8 cm
 Description:
Group of scalenohedra with inclusions topped by a large twin.
 Viewed:  23831 Time(s)

013 - Calcite Palmarejo Chinipas Chihuahua.jpg



014 - Calcite Palmarejo Chinipas Chihuahua.jpg
 Mineral: Calcite
 Locality:
Palmarejo Mine, Palmarejo, Municipio Chinipas, Chihuahua, Mexico
 Dimensions: app 10 x 10 x 6 cm
 Description:
Very interesting flat shape, disk like with the Mn inclusions visible in the center of the crystals. I only saw one specimen and it was spoken for to another collector. I sure wish to see more of these.
 Viewed:  23535 Time(s)

014 - Calcite Palmarejo Chinipas Chihuahua.jpg



015F - Calcite Palmarejo Chinipas Chihuahua.jpg
 Mineral: Calcite
 Locality:
Palmarejo Mine, Palmarejo, Municipio Chinipas, Chihuahua, Mexico
 Dimensions: app 10 x 8.5 x 4 cm
 Description:
The fluorescence, clockwise from the top left, natural light, Bright orangey red shortwave, medium pinkish red mediumwave and lesser color but still nice fluorescence at longwave.
 Viewed:  23560 Time(s)

015F - Calcite Palmarejo Chinipas Chihuahua.jpg



016F DLSW - Calcite Palmarejo Chinipas Chihuahua.JPG
 Mineral: Calcite
 Locality:
Palmarejo Mine, Palmarejo, Municipio Chinipas, Chihuahua, Mexico
 Dimensions: app 6 cm field of view
 Description:
Under natural and shortwave, one can clearly see the inner first generation highly fluorescent compared to the clear second generation.
 Viewed:  23579 Time(s)

016F DLSW - Calcite Palmarejo Chinipas Chihuahua.JPG


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Jordi Fabre
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PostPosted: Jul 19, 2015 16:29    Post subject: Re: New finds out of Mexico - (10)  

Thanks Jean, new locality added and applied!
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