Fluorspar, also known as fluorite, is a mineral with the chemical formula (calcium fluoride). It’s a common and widespread mineral that can be found in a variety of colors, including purple, blue, green, yellow, and colorless. Fluorspar is the primary commercial source of the element fluorine.
Fluorspar Properties and Types
Fluorspar is relatively soft, with a Mohs hardness of 4. It’s notable for its perfect octahedral cleavage, meaning it breaks along four different planes, often resulting in pieces shaped like octahedrons. It is also well known for its fluorescence—a property where it glows under ultraviolet light, typically a blue or violet color.
Commercial fluorspar is categorized into different grades based on its purity:
- Metallurgical Grade (Met-spar): Contains between 60% and 85% CaF2. It’s primarily used in the production of iron and steel as a flux, which lowers the melting point of raw materials and helps remove impurities like sulfur and phosphorus from the molten metal.
- Ceramic Grade: Contains 85% to 96% CaF2. It’s used in the manufacturing of specialty glass, ceramics, and enamelware to create glossy, opaque, or translucent surfaces.
- Acid Grade (Acid-spar): This is the highest-purity grade, with at least 97% CaF2. It is the primary raw material for producing hydrofluoric acid (HF).
Production and Sources
Fluorspar is mined in many countries worldwide. China is the largest producer, accounting for more than 55% of global supply. Other major producers include Mexico, Mongolia, and the United States. In the USA, commercial fluorspar deposits are found mainly in Illinois, Kentucky, and New Mexico, with Illinois historically being the largest source. Although production in the United States declined significantly in the late 20th century, new projects and strategic initiatives have been developing to reduce reliance on imports.
