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Two rocks both green, one is transparent, the none transparent rock is extremely tough almost impossible to cause a scratch on it.

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    $\begingroup$ Welcome to the site. Please, provide a picture better focused. At the smartphone you are abble to do that by touching at the rock. You may want edit your question providing further information. Where did you found it? earthscience.meta.stackexchange.com/questions/124/… $\endgroup$ – user12525 Jun 4 '18 at 18:23
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The photos are pretty bad but a couple of things still stand out, the translucent sample shows apparent conchoidal fracture which coupled with the colour and level of transparency makes me think it's green Obsidian. Obsidian is a volcanic glass and can be mistaken for manmade glass, what is sold as obsidian in many stores is in fact not a natural substance at all. Also as I should have pointed out originally without some scale and clarity the sample presented may well be a broken piece of manmade glass.

The second photo is a little clearer, the apparent fine layering and particular shade of green looks just like a sample of fused volcanic ash I have that came from Mount Tongariro.

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    $\begingroup$ Without more information (size, where found, &c) the first picture might easily be a broken piece of green glass. $\endgroup$ – jamesqf Jun 4 '18 at 18:47
  • $\begingroup$ @jamesqf That'll teach me for letting myself get distracted by link formatting, I didn't put all the information I had intended to, good spotting thank you. $\endgroup$ – Ash Jun 4 '18 at 18:53

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