mineral
Carborundum (Silicon Carbide)
Silicon Carbide (SiC) / Moissanite (natural form)
AI-generated identification · may be incorrectHardness: 9–9.5 (Mohs scale), Color: iridescent black, green, or blue with rainbow highlights, Luster: adamantine to metallic, Crystal structure: hexagonal/trigonal, Cleavage: poor/none, Specific gravity: 3.21
- Hardness
- 9–9
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Physical properties
Hardness: 9–9.5 (Mohs scale), Color: iridescent black, green, or blue with rainbow highlights, Luster: adamantine to metallic, Crystal structure: hexagonal/trigonal, Cleavage: poor/none, Specific gravity: 3.21
Formation & geological history
While rare natural Moissanite occurs in meteorites and mantle-derived rocks, most specimens like the one pictured are man-made. They are created in electric resistance furnaces using the Acheson process, which fuses silica sand and carbon at temperatures between 1,600 and 2,500 °C.
Uses & applications
Used extensively as an industrial abrasive (sandpaper, grinding wheels), in semiconductor electronics, bulletproof vests, and as a diamond simulant in jewelry (Moissanite).
Geological facts
It is nearly as hard as a diamond. The iridescent 'rainbow' effect is caused by a thin layer of silicon dioxide that forms on the surface, creating thin-film interference similar to oil on water.
Field identification & locations
Identify by its extreme hardness, jagged crystalline structure, and distinct rainbow iridescence. It is rarely found in the field naturally; most specimens are found in rock shops or industrial sites. Its high thermal conductivity and hardness are key identifiers.
