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I'm not sure if these are obsidian snowflakes:

I found it near a river, hardness is 4 to 5, it has a wax lustre when pre-polished. The 'flakes' in the matrix are raised and gray.

enter image description herePre-polished side

enter image description hereRough side

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closed as off-topic by Leukocyte, Peter Jansson, Erik, trond hansen, uhoh Sep 4 at 1:38

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    $\begingroup$ Doesn't have the appearance of Obsidian, i.e. I don't see any conchoidal fractures, although they could have been weathered away. Looks more like a porphyritic basalt, though I wouldn't expect a waxy lustre with basalt. $\endgroup$ – Friddy Jun 26 '18 at 22:20
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    $\begingroup$ I don't think neither that's obsidian glass. that hexagonal forms looks me biological/superficial. You migth be close to that ophyolite belt, and could be basalt $\endgroup$ – Leukocyte Jun 26 '18 at 22:47
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    $\begingroup$ I'm going to agree that the lustre and fracture look wrong for Obsidian, I have samples of raw obsidian at home and it's just not a good match. It does look igneous though. My guess would be either something naturally dark and fine grained, Gabbro, Basalt, Peridotite, with lighter larger Phenocrysts, or something highly altered. It does bear some resemblance to metamorphosed Basalts I've seen in Northland so that's a possibility. $\endgroup$ – Ash Jun 27 '18 at 12:14
  • $\begingroup$ there is an ophiolitic belt not far from our firend Ymer expeditions at Macedonia. looks ultrabasic igneous rock or basalt $\endgroup$ – Leukocyte Jun 27 '18 at 13:11
  • $\begingroup$ Yes...thank you... Lojane is the locality near my town with large complexes of ophiolitic rocks, peridotite...sory you know it's to much for me but for my purpose is to prove that what you are saying...east Vardar ophiolitic belt...what do you think obsidian rhyolite please... $\endgroup$ – Ymer Zumeri Jun 28 '18 at 0:45
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These appear to be plagioclase crystals in basalt, diabase, or andesite. The crystals have alteration rims, rather than a snowflake pattern.

enter image description here

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  • $\begingroup$ Hexagonal plagioclase? The white forms? $\endgroup$ – Leukocyte Jul 3 '18 at 13:01

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