Dumortierite is an orthorhombic, fibrous aluminum borosilicate mineral (Al 7 BO 3 (SiO 4) 3 O 3) that typically forms slender prismatic crystals with spectacular color and pleochroism. The crystals ...

Gem hunting, or rock hounding, is a fascinating hobby that allows people to find rare rocks and stones from amethyst and agate to sapphires and even diamonds.

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