Rough Diamond
Diamond (pure carbon variety) · Precious Gemstone
Crystal System
Cubic (Isometric); habit often octahedral, dodecahedral, or cubic, often appearing as rounded macles or irregular grains in alluvial deposits.
Mineral Group
Native Elements
Chemical Formula
C
Formation Process
Igneous/High-Pressure Metamorphic; forms at extreme depths (150-200km) in the Earth's mantle under intense heat and pressure, then transported to the surface via deep-source volcanic eruptions.
About This Crystal
A translucent to transparent olive-yellow or greenish-grey rough stone. It exhibits a greasy to adamantine luster typical of uncut diamond, with triangular growth marks (trigons) and step-like features on the surface.
Physical Characteristics
Color: Yellowish-grey; Streak: White; Cleavage: Perfect in four directions (octahedral); Fracture: Conchoidal; Specific Gravity: 3.52; Fluorescence: Often fluoresces blue under longwave UV.
Optical Properties
Refractive Index: 2.417 (Singly refractive); Dispersion: High (0.044), which causes the 'fire' seen as colorful flashes on the surface facets even in rough form.
Hardness & Durability
Origin Region
Notable sources include South Africa (Kimberley), Botswana, Russia (Siberia), Canada (Northwest Territories), and Brazil; typically found in Kimberlite pipes or secondary alluvial deposits.
Hardness & Durability
Mohs Hardness: 10 (the hardest known natural substance); Toughness: Good (though brittle if hit along cleavage planes); high stability to heat and chemicals.
Care & Maintenance
Safe to clean with warm soapy water, ultrasonic, or steam. Store separately to avoid scratching other gemstones; avoid hard mechanical impacts due to perfect cleavage.
Rarity & Value
Gem-quality specimens are rare; value is determined by the 4Cs (Carat, Color, Clarity, Cut). Fancy yellow tints are common in industrial or lower-grade jewelry rough.
Special Characteristics
High dispersion causes spectral colors (fire) on the surface; adamantine luster; potential blue or yellow fluorescence; visible surface growth patterns (trigons).
Lore & History
Historically used as a symbol of invincibility and power; the name 'diamond' comes from the Greek 'adamas' meaning 'unbreakable'. Traditionally associated with the crown chakra and eternal love.