Haiweeite

Radioactive

Haiweeite is a rare uranium mineral that belongs to the autunite group, with a chemical formula of Ca(UO2)2Si5O12·5H2O. It is a secondary mineral that typically forms through the alteration of uranium-bearing minerals in granites and pegmatites under oxidizing conditions. Haiweeite is known for its bright yellow-green color and its fluorescent properties under ultraviolet light, which make it a subject of interest among mineral collectors.

Properties and Characteristics

Haiweeite crystallizes in the orthorhombic system, displaying tabular and elongated crystals. It has a vitreous to pearly luster and exhibits a yellow to greenish-yellow color. The mineral is translucent to transparent and has a hardness of 2-3 on the Mohs scale of mineral hardness. Its fluorescence under UV light is a distinctive feature, showing bright green to yellow colors.

Occurrence

Haiweeite is found in a variety of geological settings where uranium-bearing minerals are present. It is often associated with other uranium minerals such as autunite, torbernite, and uranophane. Significant deposits of haiweeite have been discovered in the United States, particularly in the Haiwee Reservoir area of Inyo County, California, from which the mineral takes its name. Other notable occurrences include uranium mines in the Czech Republic, Germany, and Portugal.

Uses and Applications

Due to its uranium content, haiweeite, like other uranium minerals, can be a minor ore of uranium. However, its primary interest lies in the field of mineral collecting, where its vibrant color and fluorescence make it a sought-after specimen. The study of haiweeite and related minerals also provides valuable insights into the geochemical processes that lead to the formation of uranium deposits.

Safety and Handling

Handling haiweeite, as with all uranium minerals, requires caution due to its radioactivity. While the levels of radiation emitted by small specimens are generally low, long-term exposure or ingestion of dust can pose health risks. It is recommended to store uranium minerals in well-ventilated areas and to use protective equipment when handling them to minimize exposure.

See Also

• Uranium
• Autunite
• Mineral collecting
• Fluorescence
• Radioactivity