mineral

Amethyst (Purple), Sulfur (Yellow), and Blue Apatite

SiO2 (Quartz), S (Native Sulfur), Ca5(PO4)3(F,Cl,OH) (Apatite Group)

Hardness: Quartz (7), Sulfur (1.5-2.5), Apatite (5). Colors: Violet purple, bright yellow, and deep teal blue. Lusters: Vitreous (glassy) to resinous. Crystal structures range from Hexagonal to Orthorhombic.

Hardness: Quartz (7), Sulfur (1

Identified March 25, 2026More mineral →

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Physical properties

Formation & geological history

Amethyst forms in hydrothermal veins and geodes; Sulfur typically forms near volcanic vents and hot springs; Apatite is a common accessory mineral in igneous and metamorphic rocks.

Uses & applications

Amethyst and Apatite are used in jewelry and gemstone collecting. Sulfur is used industrially for sulfuric acid, fertilizers, and matches.

Geological facts

Amethyst's purple color comes from iron irradiation. Sulfur is one of the few minerals that is a pure element. Apatite is the mineral that makes up human teeth and bones.

Field identification & locations

Identify Amethyst by its purple hexagonal points; Sulfur by its distinct 'rotten egg' smell when heated and bright yellow color; Apatite by its scratch-ability with steel and teal color. Commonly found in Brazil, Sicily, and Madagascar respectively.

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