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1,799 questions

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8,432 users

I live in Menemen, Izmir, TURKEY.

0 votes

I found this one by a very small winter river. In summer it dries. Pocket knife does not mark it. Light does not pass through. Light source makes its colour lighter.

About the small ones. Today I went for more search. Little ones are parts of that big one. They happen in that red rock. Its shapes are very interesting. There are a lot of small blades (4x1mm) can you see them? I haven't seen anything like this before. They seem reddish but actualy they are whitish. The red stone around them make them see reddish. I found them on a hill. Machines worked there and broke them. They are kind of collectible. Knife marks easily on the red part. Whitish parts just a little.

The last one. I found it on a rocky hill. Knife marks it. Light passes a little. 

Thanks for help

asked Feb 12 by NafizM (220 points)

1 Answer

0 votes

The top three are very hard and I think Quartz. The chemical formula for Quartz is SiO2. It is also the chemical formula for flint, chert, chalcedony, opal, tigerseye and agate. The differences occur because of the way the crystals form under differing conditions of pressure, temperature and environment. Iron and other trace elements may stain the crystals 

Salt minerals and sandstone form minerals that are somewhat softer. I cannot yet tell what the yellow color mineral is. You say it leaves a brown streak and scratches easily. I will look some more and answer again later.

answered Feb 13 by Weasel (38,360 points)
I found them
 


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