mineral

Amethyst with Cacoxenite

Silicon Dioxide (SiO2) with Hydrated Iron Aluminum Phosphate (Fe3+24Al(PO4)17O6(OH)12 17H2O)

Hardness: 7 (Amethyst), 3.5-4 (Cacoxenite). Color: Purple quartz with needle-like brown/gold inclusions. Luster: Vitreous. Crystal Structure: Trigonal.

Hardness: 7 (Amethyst), 3
Color: Purple quartz with needle-like brown/gold inclusions
Luster: Vitreous

Identified May 9, 2026More mineral →

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Physical properties

Hardness: 7 (Amethyst), 3.5-4 (Cacoxenite). Color: Purple quartz with needle-like brown/gold inclusions. Luster: Vitreous. Crystal Structure: Trigonal.

Formation & geological history

Found in hydrothermal veins and geodes. The cacoxenite forms as inclusions within the quartz during different stages of crystallization, often found in the Super Seven deposit of Brazil.

Uses & applications

Highly valued by mineral collectors, used in lapidary work and jewelry, and popular in the metaphysical community.

Geological facts

Commonly marketed as 'Super Seven' or 'Melody Stone' when it contains inclusions of cacoxenite, lepidocrocite, goethite, and minerals other than just quartz.

Field identification & locations

Identify by looking for purple amethyst coloration containing distinct golden-brown radiating needle clusters or tufts. Commonly sourced from the Minas Gerais region of Brazil.

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