Emerald
Beryl var. Emerald · Precious Gemstone
Crystal System
Hexagonal; typically occurs in prismatic crystals, often with flat terminations, but this specimen appears as an irregular rough fragment.
Mineral Group
Silicates (Cyclosilicate)
Chemical Formula
Be3Al2Si6O18 with Chromium (Cr) and sometimes Vanadium (V) impurities
Formation Process
Hydrothermal or pegmatitic; forms where beryllium-bearing fluids interact with chromium or vanadium-rich rocks under high pressure.
About This Crystal
A translucent to opaque rough specimen with a characteristic medium to dark green color. It displays a vitreous to dull luster and a somewhat grainy, fractured surface typical of lower-grade rough emerald material.
Physical Characteristics
Color: Green; Streak: White; Cleavage: Poor/Imperfect in one direction; Fracture: Conchoidal to uneven; Specific Gravity: 2.67-2.78; Fluorescence: Neutral to reddish under UV.
Optical Properties
Refractive Index: 1.57-1.60; Birefringence: 0.004-0.009; Doubly refractive; Pleochroism: Green to blue-green.
Hardness & Durability
Origin Region
Notable sources include Colombia (Muzo, Chivor), Brazil (Minas Gerais), and Zambia. Usually found in hydrothermal veins or pegmatites.
Hardness & Durability
Mohs Hardness: 7.5 to 8.0; Toughness: Poor to Fair (brittle due to inclusions/fissures); Stability: Generally stable but sensitive to thermal shock.
Care & Maintenance
Avoid ultrasonic and steam cleaners. Clean with warm, soapy water and a soft brush. Keep away from harsh chemicals and high heat which can cause internal fractures to expand.
Rarity & Value
Common as low-grade opaque rough; extremely rare and valuable as transparent, high-clarity gem material. Values depend on color saturation and clarity.
Special Characteristics
Often contains 'jardin' (internal inclusions resembling a garden). This specimen shows typical internal fracturing and zoning within the green mass.
Lore & History
Historically prized by ancient Egyptians, Incas, and Aztecs. Traditionally associated with the Heart Chakra, it is often called the 'Stone of Successful Love' in lore.