Garnet (likely Almandine or Pyrope-Almandine series)
Almandine Garnet (IMA-approved) · Semi-Precious Gemstone / Mineral Specimen
Crystal System
Cubic (Isometric); occurring as dodecahedron or trapezohedron, though featured here as a polished sphere.
Mineral Group
Silicates (Nesosilicates); Garnet Group
Chemical Formula
Fe3Al2(SiO4)3; often contains traces of magnesium or manganese
Formation Process
Metamorphic; forms under high pressure and temperature during the regional metamorphism of clay-rich sedimentary rocks.
About This Crystal
A polished sphere approximately 20mm in diameter. It displays a deep purplish-red to brownish-red color, appearing near-opaque in thick sections but translucent where light hits the edges. Shows a vitreous luster.
Physical Characteristics
Color: Dark red to burgundy; Streak: White; Cleavage: None (indistinct); Fracture: Conchoidal to uneven; Specific Gravity: 3.9 - 4.3; Tenacity: Brittle; Fluorescence: Generally inert.
Optical Properties
Refractive Index: 1.770–1.820; Singly refractive (Isotropic); Pleochroism: None; Dispersion: 0.027 (low).
Hardness & Durability
Origin Region
Prominently India, Sri Lanka, Madagascar, and Brazil; forms in regional metamorphic rocks like mica schists.
Hardness & Durability
Mohs Hardness: 7.0 - 7.5; Toughness: Fair to Good; Stability: Highly stable to light and most chemicals; sensitive to extreme thermal shock.
Care & Maintenance
Clean with warm soapy water and a soft brush. Avoid ultrasonic cleaners if the stone has internal fractures. Store away from harder stones like sapphire or diamond.
Rarity & Value
Common; Value is determined by color saturation and clarity. Deep red almandines are affordable, typically ranging from $5 to $50 for small polished items like this sphere.
Special Characteristics
May exhibit minor asterism (star effect) if oriented correctly with rutile needle inclusions, though not visible here. Exhibits characteristic iron absorption bands under a spectroscope.
Lore & History
Historically used as a talisman for protection in ancient Rome and Egypt. Traditionally associated with the Root Chakra, representing strength, security, and physical vitality in modern crystal lore.