FMF - Friends of Minerals Forum, discussion and message board

[Singingstone48]

I recently bought a calcite specimen on Ebay that came with two old labels that only said Durango, Mexico. I have searched all the Mindat localities for calcite in Durango and the other states near it, and have not seen any images in that database that correspond to the features of this specimen. I have seen hundreds of Mexican calcite specimens over the years I have been collecting and have never seen anything quite like this specimen, which is why I bought it. I like to be as precise as I can about localities on my labels. I have attached several photos of the specimen. Hopefully someone with more experience can point me towards a good locality, more than just a state name.

[Peter Megaw]

The coating is specular hematite???

Did this come from Carlos Garcia Gutierrez's collection?

[Singingstone48]

Peter,
I'll need to put this under my scope and check it out. Hematite. Hmm. I was thinking Manganese oxides but maybe you are right. The dealer I got it from had two old labels with the Durango, Mexico info, but neither label had any information on collector, dealer or shop where it had come from. I'm not familiar with the collection you named. I'll get back when I can determine whether the coating is hematite or not.

[Peter Megaw]

A light scratch on an inobtrusive place on the black stuff will go "indian-red-brown" if it's hematite...and stay black if its manganese. If it's specularite you should get red internal reflections with a scope or a good lens

[Carlos M.]

Hi friends.

That´s a nice calcite. I have a similar specimen from the Ojuela mine... it came out from the mine a few years ago.
It's a dogtooth calcite with goethite coating.

Hope it would help.

[Jean Sendero]

Ojuela! Interesting.

I had not seen this crystal form for calcite from the Ojuela before.

Carlos do you have a better timing as to when these came out, more or less, better than a few years ago? Or even a location in the mine?

Thanks

J

[Carlos M.]

Well, Jean I wouldn't know when and where exactly it came out from. But I bought it 4 years ago to a dealer friend of mine...

He had a small flat of those calcites...