Gem Detector Machine

20191126a gemstone also called a gem, fine gem, jewel, precious stone, or semiprecious stone is a piece of mineral crystal which, in cut and polished form, is used to make jewelry or other adornmentsowever, certain rocks such as lapis lazuli and opal and occasionally organic materials that are not minerals such as amber, jet, and pearl are also used for jewelry and are therefore often.

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