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Jewelry, Gems, & Minerals/Help me identify 2 types of stones

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Small, polished
Small, polished  

Large raw stone or mineral
Large raw stone or min  
I checked my books, searched sites for pics but I'm still unable to identify these 2 stone types. One stone type, I have 3 of. They are small and jewelry sized. They have turquoise, white and reddish marks. They are polished. The other stone I just acquired last night. I know it is not common to see this stone in such a large size and in its raw form. It is rough, non-translucent,. It is deep blue in spots and green. There are also golden tan colors. I don't want to clean it, in fear of losing mineral deposits from it. Iim a collector for many years and I am stumped.. Can you please help me??

Answer
Polished stones are notoriously difficult to identify without the actual specimen in hand, because unfortunately polishing removes many diagnostic features from the stone that could give clues about the stones identity. For your three little stones I am really taking a stab in the dark, but it looks like a mixture of jasper (red microcrystalline quartz) and possibly some copper mineral (blue; turquoise?!?) While I am somewhat certain about the jasper, I could be way off on the rest.

The larger stone looks like a composition of secondary copper minerals from the oxidized zone of a mineral deposit. The blue material is most likely azurite (Cu3(CO3)2(OH)2) and the green is malachite (Cu2(CO3)(OH)2). Both of these minerals do occur frequently together as in your sample. The yellowish brown material is probably a mixture of various iron oxides (goethite, limonite, hematite). The strange smell is most likely the result of sulfur from the decomposing original sulfide minerals. This rock would be sensitive to cleaning, especially acids. Azurite and malachite, both copper carbonates, will be readily attacked by acids, even weak ones.

Jewelry, Gems, & Minerals

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Uwe Richard Kackstaetter, Ph.D. (Dr.K)

Expertise

I can answer questions concerning minerals, mineralogy, gems, metals, and anything that has to do with geology. However, I am NOT a jeweler. Questions about values, settings, gem stone cuts and appraisals are best directed to other experts on this site. I can however aide in the identification of unknown mineral materials. As a public service and part as training for new geoscientists, our university department provides FREE mineral identification for individuals. Please contact me for details or go to http://college.earthscienceeducation.net/MIN/MINID.pdf for details..

Experience

I am a professor of applied geology and mineralogy with many hours of field experience. Furthermore, I enjoy recreational gold prospecting and mineral collecting. As a professor I am engaged in research concerning minerals and their occurrence.

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Member of the GPAA (Gold Prospectors Association of America) as well as the Association of Environmental Geochemists. Member of the GSA (Geologic Society of America) Member of the AIPG (American Institute of Professional Geologists)

Publications
Here is a small sampling: Mineral-rock handbook: Rapid-easy mineral-rock determination : written for anyone interested in minerals and rocks - Proctor, Peterson, and Kackstaetter;Macmillan Pub. Co. (New York and Toronto and New York) Physical Geology Laboratory e-Manual [CD-ROM], Kackstaetter, Earth Science Education LLC Colorado Front Range Self-guided Geology Field Trips, Kackstaetter, http://www.scribd.com/doc/27175290/Colorado-Front-Range-Self-Guided-Geology-Field-Trips

Education/Credentials
Ph.D. in Applied Geology and Mineralogy. I am actively teaching courses in mineralogy and a variety of field courses with mineral collecting opportunities. Background in precious metal exploration.

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Numerous!

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