Currently the Altyn-Tyube page list Calcite, Dioptase, and Quartz.
One of the Dioptase specimens in my collection is a group of mediocre dioptase crystals on calcite and two patches of an unidentified green needle shaped mineral. Th needles are a transparent, glassy emerald green and range up to about 1.5mm long Does anyone know enough about the area to suggest what this mineral may be?
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unidenti green needles Altyn-tyube 1mm xls.jpg (144.4 KB)
I suspect that it's acicular Malachite. In the past I have identified both Malachite and Azurite on some of my Altyn-Tyube Dioptase specimens. Malachite on these specimens were found both as acicular needles on some specimens and pseudos after Azurite on one specimen, shown here: http://www.mindat.org/forum.php?read,11,198041,198066 . I don't know if you have enough material to test a bit of it with dilute HCl to see if it fizzes but that may help if possible to do. Good luck with it Karl.