Image: James St. John (CC BY 2.0)
trigonalrareOxides
Ruby
Al2O3
The image displays a deep red, often hexagonal or barrel-shaped crystal of ruby, a variety of corundum, known for its vibrant color and high transparency in gem quality specimens.
Ruby Physical Properties
Mohs Hardness
9Crystal System
trigonalLuster
vitreousStreak Color
whiteCleavage
none (parting present)Fracture
conchoidalSpecific Gravity
4Colors
red, pinkish-red, purplish-redTransparency
transparentType Locality
Mogok (Myanmar), Thailand, Sri Lanka, Tanzania, MadagascarMineral Group
OxidesUses
jewelry, laser technology, watch bearings, abrasivesAssociated Minerals
calcite, phlogopite, spinel, garnet, kyaniteRarity
rareGeological Context
Ruby forms in metamorphic rocks such as marble and gneiss, as well as in some igneous rocks like basalt and syenite. It is often found in secondary alluvial deposits due to its extreme hardness and resistance to weathering.
