Hardness : it barely scratches glass, can't scratch gorilla glass of my lg g2

Transparency : translucent, you can see the flashlight of a smart phone.

Luster : it has glassy luster. Shiny surfaces.

Density : it is light like a piece of aluminum or even lighter a bit.

Streak : it has white streak. Smells like a matchhead when I slide it through a surface of quartz.

Location: It was found by a shepherd from a northeast Anatolian village


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closed as off-topic by EnergyNumbers, Jan Doggen, BillDOe, Semidiurnal Simon, Erik Oct 21 at 13:43

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  • 2
    $\begingroup$ Does it have concoidal fracture? It sounds like obsidian to me. $\endgroup$ – bon Sep 16 '16 at 8:09
  • 1
    $\begingroup$ 1. Trying to use your phone's glass as hardness test is a bad idea. 2. Any chance of uploading a picture? $\endgroup$ – Gimelist Sep 16 '16 at 8:25
  • $\begingroup$ Obsidian sound like a good guess. Depending on where it was found, maybe man-made glass? $\endgroup$ – Tactopoda Sep 16 '16 at 12:47
  • 1
    $\begingroup$ @Tbb It was found by a shepherd of my village :) which is a northeast anatolian village $\endgroup$ – Ahmet Bilal Sep 16 '16 at 13:04
  • 1
    $\begingroup$ This question shouldn't be closed. It has 4 upvotes because of inertia, but it is uncongruent with our speach to close this. Maybe my mistake. I retracted my vote. Thanks for the edit @uhoh $\endgroup$ – user12525 Jul 13 at 12:28

I would bet that Bon and Tbb are both 'spot on'. The hardness, black colour, conchoidal fracture and sharp edges are all typical of obsidian. Many obsidians are smokey to bottle green in transmitted light. Also, the location of northeast Anatolia is another giveaway. Obsidian is a glass that devitrifies over time, so we only find it in areas of relatively recent volcanic activity. Northeast Anatolia is indeed noted for its historic volcanism. Nemrut, in eastern Turkey is the most famous volcano, erupting as recently as 1441, and is known to produce obsidian. There are also a few other smaller volcanic centres in the region, any of which could contain some obsidian. Those with an eye for geological detail may be able to spot the most obvious on Google Earth. Hint - there is a line of at least 5 volcanoes between western Lake Van and Mount Ararat in Armenia. There are others, mostly less obvious, further north in Eastern Turkey.


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