gemstone
Diamond and Sapphire
Carbon (Diamond, C) and Aluminum Oxide (Sapphire, Al2O3)
AI-generated identification · may be incorrectDiamond has a hardness of 10 on the Mohs scale, adamantine luster, and cubic crystal structure. Sapphire has a hardness of 9, vitreous to adamantine luster, and trigonal crystal structure.
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Physical properties
Diamond has a hardness of 10 on the Mohs scale, adamantine luster, and cubic crystal structure. Sapphire has a hardness of 9, vitreous to adamantine luster, and trigonal crystal structure.
Formation & geological history
Diamonds form deep within the Earth's mantle under extreme pressure and temperature, brought to the surface via kimberlite pipes. Sapphires form in metamorphic or igneous rocks like basalts and pegmatites.
Uses & applications
High-end jewelry, industrial cutting and grinding tools, and technological applications.
Geological facts
Diamond is the hardest known natural material on Earth, while sapphire is a variety of corundum known for its deep blue color caused by trace amounts of iron and titanium.
Field identification & locations
Identified by extreme hardness, high refractive index, and distinct crystal or cut facets. Commonly found in jewelry settings.
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