This is turquoise which did not harden and is extracted in chunks of soft turquoise called chalk because being soft and is kind of white when dry and blue when wet. This is later stablized or hardened, but in the process of transporting it from the mines to town first and later to the buyers and other places, it breaks and small pieces remain in the sacks or boxes, these small pieces you put together and compress into blocks that are later hardened. "This is compressed turquoise". I myself made some and still have some compressed turquoise and other.
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