gemstone

n. gem, jewel, precious stone

GemStone can mean:Gemstone, a type of mineralGemStone IV (or GemStone III), an online multiplayer game by Simutronics CorporationGemStone Systems, a data management company
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A gemstone, gem or also called precious or semi-precious stone is a highly attractive and valuable piece of mineral, which — when cut and polished — is used in  jewelry or other adornments. However certain rocks, (such as lapis-lazuli) and organic materials (such as amber or jet) are strictly speaking not minerals, but are still applied in jewelry and adornments, and are therefore often considered a gemstone as well. Some minerals that are too soft to be generally applied in jewelry may still be considered a gemstone because of their remarkable color, lustre or other physical properties that have aesthetic value. Rarity is another characteristic that lends value to a gemstone.
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Noun
1. a crystalline rock that can be cut and polished for jewelry; "he had the gem set in a ring for his wife"; "she had jewels made of all the rarest stones"
(synonym) gem, stone
(hypernym) crystal
(hyponym) cabochon
(part-holonym) jewelry, jewellery