Diamond

Hardness: 10 (Mohs scale), Color: Typically colorless or with tints of yellow, brown, green, gray, blue, purple, pink, red. Luster: Adamantine (bright, like a diamond). Crystal Structure: Isometric (cubic), often forming octahedra, dodecahedra, or cubes. Cleavage: Perfect octahedral cleavage, but rarely observed due to its hardness. Specific Gravity: 3.52.

Formed in the Earth's mantle at depths of 150-200 km, transported to the surface by deep-source volcanic eruptions (kimberlite and lamproite pipes). The formation process occurs over millions to billions of years (typically 1 to 3.3 billion years old). They are found in ancient cratons, which are stable continental blocks.

Industry: Abrasives (cutting, grinding, drilling), polishing agents, heat sinks in electronics, optical windows. Jewelry: Highly prized as gemstones due to their brilliance, fire, and hardness, used in rings, necklaces, earrings, and other ornaments. Collecting: Rare and large diamonds are highly valuable collector's items.

Diamonds are the hardest known natural material. They form under extremely high pressure and temperature conditions deep within the Earth's mantle (about 150-200 km deep). The word 'diamond' comes from the ancient Greek word 'adamas', meaning 'unbreakable' or 'invincible'. The largest diamond ever found was the Cullinan Diamond, weighing 3,106 carats (621 grams), discovered in South Africa in 1905.

In the field, identifying a rough diamond can be challenging without specialized equipment. However, key indicators include its extreme hardness (it will scratch virtually any other material), its high specific gravity, and its characteristic adamantine luster. Rough diamonds often have a greasy appearance and may exhibit trigons (triangular growth marks) on their faces. Major sources include Russia, Botswana, Canada, Australia, and South Africa. For collectors, understanding the '4 Cs' (carat weight, cut, color, clarity) is crucial for evaluating polished diamonds. Rough diamonds are sought after for their rarity and potential to reveal the crystal's natural form.