FMF - Friends of Minerals Forum, discussion and message board

[Carles Millan]

[Jordi Fabre]

Correct, I already added "Hematite after Magnetite" to Samuel's text.

Thanks for your contributions Samuel, as well as for your didactic and comprehensible descriptions.

Jordi

[Samuel]

Hi Carles:

Thank you for pointing that out. I think I might have cut and paste the name from Mindat. Sometimes it is hard because IMA does not always conform to proper nomenclature that an Inorganic Chemist might use, so at times it depends if you are talking as a mineralogist/geologist or an Inorganic/Organometallic Chemist. You must understand Carles I am a pilgrim and I try to make minerals fun for all. I do not want to be too strict, as it might scare some people too much. I actually like the term Martite, it is good and old fashioned just like "Kidney Ore."

[Samuel]

This is a beautiful Tetrahedrite and not easy to photograph – the crystals look like mirrors. It contains large and well formed Tetrahedrite crystals along with what could be Sphalerite. Like the other specimen from Casapalca the matrix also contains fine-grained pyrite. This one is 16 x 14 x 6 cm and the largest Tetrahedrite is about 4 cm. I have included some macro shots, which show just how technically stunning the specimen is. It hails from Casapalca Mine, Casapalca, Huarochiri Province, Lima Department, Peru.

PS: I also have some great samples, and some stunning photographs of the adjacent Yauli Yacu Mine, both surface and underground photos but I must first get permission from the operators of the mine. When they gave them to me I did promise not to publish unless I first got their approval.

[Samuel]

Dear Jordi:

Thank you for the encouraging words. I hope I do not instruct too excessively. I have always thought of myself as more eclectic, hence my interest in many fields, principally chemistry, physics, electronics and astronomy. I also have an interest in the arts, mainly the history and philosophy of science, and I am now a keen photographer having recently acquired a 10MP Fuji camera.

[GneissWare]

Samuel,
Keep up the posts..just as they are. I am enjoying your commentary, and unique take on minerals, the business of minerals, etc. Great job!
Bob

[Samuel]

Hi Bob, thank you for your encouraging words, it does help.

This is another Bolivian piece I have. It consists of Magnetite on matrix. The crystals are black but with a beautiful metallic luster. It is 17 x 10 x 3 cm and hails from Cerro Huañaquino, Potosí Department, Bolivia. The largest crystal is about 1.5cm. I feel these are a great specimen to acquire if you do not have a lot of money to spend. You can get some amazing pieces, even as large as or larger than the one featured below for little outlay. Of course I recommend “comparison” shopping. I acquired my one for $150, but I have seen equivalent size pieces going for 5 or 6 times as much. Use the same principle as if you were shopping for a used car – don’t buy the first one you see, see if others have better for a lower cost.

[Samuel]

Feature below is one of my “common” ore samples. I have two mineral collections. The first contains the nice crystal specimens and the other the ore samples, though some ore samples are nice to look at. The mineral below is Malachite and it hails from Red Dome Mine, Chillagoe, Herberton District, Queensland, Australia. It is 10 x 7 x 5 cm, and has an amazing chatoyant luster.

[Samuel]

This is another piece I have from the Red Dome Mine. To digress slightly most of the specimens I have from Red Dome are Native Coppers, but I do have a large (8 x 6 x 4 cm) Cuprite. The specimen shown below is a floater - botryoidal malachite attached to a little piece of matrix. As can be seen in the bottom photo it also has some native copper. Like the other malachite I posted it is very chatoyant. It hails from the Red Dome Mine, Chillagoe, Herberton District, Queensland, Australia. It is 6 x 3 x 3 cm

[Samuel]

This is another piece from the Yaogangxian Mine in China – Bournonite. I had lusted, craved and yearned for one of these beauties for years, but always considered them too expensive, and thus too elusive. I have always been impressed by the English Classics from the Herodsfoot Mine, but again too much for a humble retiree to afford. I was able to secure this “babe” for about $150USD – again shop around! It has a very minor chip on one of the crystals but nothing that detracts from its inherent beauty. It is from the Yaogangxian Mine, Yizhang County, Chenzhou Prefecture, Hunan Province, China. It is 4 x 4 x 3 cm.

ps: Since acquiring this piece thanks to Jack Crowley I have also got one of those lovely Peruvian Bournonite clusters - great!!!

[Samuel]

This is an interesting piece from the Yaogangxian mine, and this time I did hit the “jackpot” in my humble opinion. It is an Arsenopyrite/Stannite (verified) combo with a little chalcopyrite - absolutely cute. Just look how sharp those arsenopyrites are – they would cut paper in my opinion, and the crystals are so lusterous you could shave by them. It is 8 x 4 x 2 cm and hails from the Yaogangxian Mine, Yizhang County, Chenzhou Prefecture, Hunan Province, China. I have always found my best photos are done outside under the shade, and so I am in the process of building light box and shades appropriate for outdoor photography.

[Samuel]

This is a rather lovely piece. It is an ore sample of Galena on matrix from the Hellyer Mine in Tasmania, which I acquired some years ago. This is what I consider a decorator piece - there are no crystals just a large shiny mass of galena. A geologist friend who had a look at it believes the galena curves as it does (see right hand photo) because of a high content of silver, which was later proven by analysis. It is 16 x 14 x 6 cm and hails from the Hellyer-Que River Mine, Waratah District, Tasmania, Australia.

[Samuel]

The specimen featured below was a welcome addition. I have quite a few arsenopyrites from China but I was literally “screamin” for one from Peru. Jack Crowley directed my attention to this piece and so I bought it. Just look at the inserts – the crystals are sharp, striated and lusterous, and just get a load of those two Sphalerites – amazing. It hails from the Pucarrajo Mine, Huallanca District, Bolognesi Province, Ancash Department, Peru. 10 x 7 x 5 cm. Since getting it I have been on the lookout for a fine Lollingite, but alas none available – perhaps it is time to start “screamin again” – smiling!!

For those really keen on Sulphide Minerals I can highly recommend the book entitled, “Reviews in Mineralogy & Geochemistry Volume 61, Sulphide Mineralogy and Geochemistry, David J. Vaughan, Ed. It is published by the Geochemical Society and the Mineralogical Society of America. And please do not let the title put you off – it has some great information and diagrams.

[Samuel]

Featured below is a specimen of Galena, Sphalerite and Quartz. It hails from the Stari Trg Mine, Trepca Complex, Trepca Valley, Kosovska Mitrovica, Kosovo. It is 12 x 9 x 4 cm. To the right are some macro shots. Some very beautiful sulphides came out of this mine and I hope to acquire some more minerals in the next year or two.

For those who might not know, I have been interested in minerals for many years but only started collecting seriously in the last two years. So what I post are recent acquisitions. In the early days I collected ore specimens. Now I concentrate on minerals from China, Bulgaria, Peru and Bolivia. I have a few English pieces and some nice Italian hematites from Elba.

As for my pictures if you wish to use them feel free to do so. I hope they will bring you as much pleasure as they have brought me.

[Samuel]

This is one of my current projects and with it I hope to find some great Uranium minerals. I have some great examples of Uraninite and Torbernite from the old Rum Jungle mine. My dad got them for me a long time ago. But with this device I hope to find more in the Flinders Ranges. The GM tube is powered by 500V, but at low current, so if I touch it I get a jolt but nothing that can kill me - smiling. One left hand side is the analog circuit, which is a GM counter in its own right. On the right hand side is the Digital counting circuit. It used a LCD and PIC16F628A microcontroller. The software code is written into the microcontroller and it does all the maths – neat!! At the moment it is counting background radiation over a period of 60 seconds and then displays the result on the LCD. Even though the scale is uS/hr it means nothing as the unit has not been calibrated. The first task is to get it all working. Also shown in the picture is a Pancake GM tube and a few Russian GM tubes.

I am very much a person who believes in the old saying, “give a man a fish and you have given him a meal for a day, teach him how to fish and you have given him food for life” and this also applies elsewhere. I build my own computers and a lot of my Electronic stuff and I know how to repair and maintain a car. The money I save is then used to buy minerals – neat!!

[Samuel]

I just love Chinese Sphalerite; they have such stunning colour and luster. The one shown below contains Sphalerite on a Quartz matrix. The back of the specimen is covered in light yellow calcite crystals covering more Sphalerite. It hails from Kangjiawan Polymetallic Deposit, Shuikoushan Ore Field, Changning County, Hengyang Prefecture, Hunan Province, China. It is 12 x 10 x 4 cm. The largest crystal group is about 5 x 3 cm. As the macro inserts show it has some amazing shapes, textures and colours, and when back lit it is stunning – in my opinion.

[Samuel]

One of the most display quality minerals you can get from “Oz” is Crocoite, and it is indeed beautiful. In fact most Chromium bearing chemicals have vibrant, beautiful colours in my opinion and experience. I have a few of the Crocoite clusters composed of stout terminated crystals but the other day I found a few individual crystals tucked away in the back of a drawer – a dozen in fact. The one featured below is about 1 x 0.7 x 0.7 cm. It hails from the Adelaide Mine, Zeehan Mining District, Dundas, Tasmania, Australia.

[Samuel]

The specimen featured below is said by some to be rare, Gaspeite, (proven by analysis) and it hails from the Kambalda Nickel Mine, Kambalda, Coolgardie Shire, Western Australia, Australia. It is 9 x 5 x 2 cm. Some years ago before the Internet, and when I did not know other countries produced great and better minerals I had a “love affair” with Australian Ore minerals, and for a brief time had a “romance” with Nickel ores - smiling. The specimen below was given to me after persistent “bugging” by me of a geologist at the Nickel mine. I do apologize for the bad photo, it is an old one.

[Samuel]

This is another Australian mineral and please forgive the photography I had to capture the proverbial “Kodak Moment” before the sunset, and as you can imagine I had to be quick. It is a native copper from the Burra Burra Mine (ca. 1870) that I acquired through an American dealer. It is 9 x 7 x 6 cm and hails from the Burra Burra Mine, Burra, Mt Lofty Ranges, South Australia, Australia. The insert shows that the base is a mass of small copper crystals.

[Samuel]

This is an interesting piece. It is a well formed and very lusterous Pyrite crystal on “Rose” quartz. The Pyrite looks like gold and it has beautiful striations as the right hand insert show. Tucked away in the left hand side of the specimen are some more pyrites – cute! It is 11 x 6 x 6 cm and the pyrite crystal is about 5 cm wide. It hails from the Morococha Mine, Morococha District, Yauli Province, Junin Department, Peru.