Botallackite

Botallackite is a rare copper mineral with the chemical formula Cu₂Cl(OH)₃. It is noted for its striking green color and is named after the Botallack Mine in Cornwall, United Kingdom, where it was first identified. Botallackite belongs to the halide minerals category and forms in the oxidation zones of copper deposits, often associated with other copper minerals such as atacamite and paratacamite.

Properties

Botallackite crystallizes in the monoclinic crystal system. It typically occurs as crusts or aggregates of small crystals. The mineral is soft, with a Mohs hardness of 3, and has a specific gravity of around 3.6. Its green color can range from bright to dark shades, depending on the specimen. Botallackite is also known for its solubility in acids and its occurrence in marine environments, where it can form as a result of the action of sea water on copper-bearing rocks.

Occurrence

Apart from its type locality in Cornwall, botallackite has been found in various locations around the world, including Australia, Chile, and the United States. It is often discovered in areas with a history of copper mining or in geological settings where copper minerals are naturally exposed to oxidizing conditions.

Uses

Due to its rarity and aesthetic appeal, botallackite is primarily sought after by mineral collectors. It does not have significant industrial uses but serves as an interesting specimen for study within the fields of mineralogy and geology.

See also

• Copper mining in the United Kingdom
• List of minerals
• Halide minerals