Metatorbernite

Metatorbernite is a mineral that belongs to the phosphate group, specifically the uranium phosphates. It is a secondary mineral that forms through the alteration of another uranium mineral, torbernite, by dehydration. Metatorbernite has the chemical formula Cu(UO₂)₂(PO₄)₂·8H₂O, which changes to Cu(UO₂)₂(PO₄)₂·8H₂O upon dehydration, indicating the loss of water molecules.

Properties

Metatorbernite is known for its distinctive green color, which can range from bright green to a deeper green hue, depending on the specimen. It crystallizes in the tetragonal crystal system, forming thin, square plates or tabular crystals that are often found in radiating or layered aggregates. The mineral exhibits a vitreous to pearly luster and has a hardness of about 2.5 to 3 on the Mohs scale of mineral hardness, making it relatively soft. It is also radioactive, due to its uranium content, which is a common trait among uranium minerals.

Occurrence

Metatorbernite is typically found in the oxidation zones of uranium-bearing ore deposits, where it occurs as a secondary mineral. It forms through the alteration of torbernite, another copper-uranium phosphate mineral, when it loses water from its structure. This process can occur under arid conditions or when the mineral is exposed to air for extended periods. Metatorbernite is often associated with other uranium minerals, such as autunite, uranophane, and its precursor, torbernite. Significant deposits of metatorbernite have been found in various locations around the world, including the Democratic Republic of the Congo, France, Germany, and the United States.

Uses

Due to its uranium content, metatorbernite has been of interest primarily for its potential as a uranium ore. However, its use is limited by the relatively small size of the crystals and the specific conditions required for its formation. In addition to its potential ore value, metatorbernite, like other uranium minerals, is sought after by mineral collectors due to its vibrant color and unique crystal formations.

Safety

Handling metatorbernite, as with all radioactive minerals, requires caution. It is advisable to store radioactive minerals in well-ventilated areas and to use protective equipment, such as gloves and masks, when handling them to minimize exposure to radiation and prevent ingestion of radioactive dust.

See Also

• Torbernite
• Phosphate minerals
• Uranium
• Radioactivity in minerals