Baryte on fluorite – Xiefang Mine, China
Locality: Xiefang Mine, Ruijin Co., Ganzhou, Jiangxi, China
Weight: 555g
Dimensions: 9,7 x 8,3 x 4,3 cm
| Category: | Baryte |
|---|
Baryte on Fluorite from the Xiefang Mine
This attractive collector's specimen comes from the Xiefang Mine in Jiangxi Province, China. The locality is well known for producing high-quality hydrothermal minerals, especially barite, fluorite, quartz and calcite.
Appearance of the Specimen
The specimen is dominated by honey-yellow to golden tabular baryte crystals. The crystals are translucent, display a vitreous to pearly luster, and create a striking contrast with the light gray to colorless fluorite. The fluorite forms the older part of the specimen, filling the cavity with a fine crystalline druse. Baryte later crystallized on its surface, which is why this type of specimen is referred to as baryte on fluorite.
Formation of the Mineral Association
The specimen formed from hydrothermal fluids circulating through fractures in the host rock. Fluorite crystallized first. After a change in the chemical composition of the fluids, Baryte began to grow on its surface. This sequence produced an attractive association of two distinct minerals. baryte has the chemical formula BaSO₄ and is characterized by its high density and tabular crystal habit. Fluorite has the chemical formula CaF₂, a Mohs hardness of 4, and perfect octahedral cleavage.