Many artists would be interested in obsidian. I would suggest speaking with the owners of any and all of the metaphysical stores to find buyers. Many of them have relationships with local artisans and can take your information and pass it along. Do not limit yourself to just one of the metaphysical stores though. Find ones that have a plethora of locally crafted products in their stores as you'll have better success that way. Good luck.
How big
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