mineral

Amethyst and Peridot

Amethyst (SiO2 with iron impurities) and Peridot ((Mg, Fe)2SiO4)

Amethyst: Hardness 7, Purple color, Vitreous luster, Hexagonal crystal system. Peridot: Hardness 6.5-7, Olive green color, Vitreous/Oily luster, Orthorhombic crystal system. Both have specific gravity around 2.65-3.4.

Identified January 22, 2026More mineral →

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Physical properties

Formation & geological history

Amethyst forms in hydrothermal veins or geodes within volcanic rocks. Peridot forms deep in the Earth's mantle and is brought to the surface by volcanic activity (igneous environments) or found in meteorites.

Uses & applications

Primarily used as gemstones in jewelry, decorative carvings, and as popular specimens for mineral collectors due to their vibrant colors.

Geological facts

Amethyst was once considered as valuable as diamonds until large deposits were found in Brazil. Peridot is one of the few gemstones that exists in only one color; it is also the birthstone for August, while Amethyst is the birthstone for February.

Field identification & locations

Identify Amethyst by its purple hue and quartz-like crystal habit. Identify Peridot by its distinct yellowish-green color and lack of cleavage. In the field, look for them in basaltic volcanic sites or mineral-rich quartz veins.

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