I picked up these slabs from a rock dealer for $20... I can tell that there is some chert, agate and obsidian but what type and are there other types of rock that I am over looking... For reference the tiles (linoleum marble
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) is 8"x4".
Also I think some of the rocks have a protective spell over them, since I have a great fear and anxiety of knapping some of the prettier ones!
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