What is Brochantite?
Brochantite is one of the most attractive secondary copper minerals. Its saturated green colour and fine sprays or crusts often occur with azurite, malachite and other oxidation-zone minerals.
Mineralogy and structure
The formula is Cu4SO4(OH)6. Brochantite crystallises in the monoclinic system, has hardness around 3.5-4 and a relatively high specific gravity for a green mineral.
Colour and appearance
Colours range from bright emerald and grass green to deep green. Crystals are commonly slender, acicular or prismatic, forming sprays, crusts and botryoidal aggregates with vitreous or silky lustre.
Formation and localities
Brochantite forms in the oxidised zones of copper sulphide deposits, especially under arid conditions. Notable localities include the Urals, Mexico, Namibia, Greece, Chile, Australia and the United States.
Collecting and care
Fine sprays are fragile and should be protected from touching and vibration. Keep the specimen dry and describe any associated malachite, azurite or linarite separately.
Brochantite and zodiac signs
Popular crystal guides often associate Brochantite with Taurus or Scorpio because of its green colour and copper origin. These links are cultural rather than scientific.
Symbolic and esoteric associations
Esoteric descriptions may present brochantite as a symbol of renewal and vivid natural colour. This is a personal or cultural interpretation, not a proven effect.
