What is Brucite?
Brucite is magnesium hydroxide and a common alteration mineral in magnesium-rich rocks. It can form pale pearly plates, green masses or fibrous aggregates with a distinctive silky appearance.
Mineralogy and structure
Brucite has the formula Mg(OH)2 and crystallises in the trigonal system. Its hardness is only 2.5-3, and perfect basal cleavage reflects its layered structure.
Colour and appearance
Colours include white, colourless, green, blue and yellow. Platy and foliated crystals have pearly lustre, while fibrous material may be silky. The fibrous variety is known as nemalite.
Formation and localities
Brucite forms during serpentinisation and alteration of periclase in marbles, ultramafic rocks and hydrothermal systems. Notable localities include Pakistan, Russia, Canada, the United States, Italy and Austria.
Collecting and care
Brucite is soft and can be scratched easily. Protect plates from bending and keep fibrous material intact; do not create dust or cut unknown fibrous specimens.
Brucite and zodiac signs
Popular crystal lists sometimes associate Brucite with Taurus or Cancer because of its green-white colour and connection with magnesium-rich rocks. These are symbolic links only.
Symbolic and esoteric associations
Esoteric descriptions may connect brucite with calm, flexibility and renewal. These themes are cultural and should not be used as medical promises.
