They're sourced from mines in the NC mountains and 2 mines close to the line in TN.
I concur with the other answers and add that they recycle as well. I was surprised and disappointed to see that they recycle the remnants from paying gem'ers to refill their buckets and use for the next influx of patrons.
We were told some of the rocks that were not available locally came from South America.
If you go to their website, it mentions that they are mined at a few different mines in the area. I think it may say where if you read more thoroughly.
I was told numerous mines, all native to NC.
They told us they are gotten from a mine in the mountains.
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