Blue Sapphire
Corundum var. Sapphire · Precious Gemstone
Crystal System
Trigonal system, typically forming barrel-shaped, bipyramidal, or tabular crystals; often tumbled or polished as in this specimen.
Mineral Group
Oxides
Chemical Formula
Al2O3 (with trace amounts of Fe, Ti, Cr)
Formation Process
Igneous and metamorphic processes; typically forms in silica-deficient rocks such as syenites, pegmatites, or metamorphosed marbles under high temperature and pressure conditions.
About This Crystal
A small, deep royal blue tumbled stone with high transparency and a vitreous to sub-adamantine luster. The surface is smoothly polished into an irregular rounded shape, exhibiting rich blue color saturation and internal light reflections.
Physical Characteristics
Deep royal blue body color, white streak, no true cleavage (exhibits parting on basal planes), conchoidal fracture, specific gravity around 4.00, brittle tenacity, generally inert to UV fluorescence though some variations may show weak red.
Optical Properties
Doubly refractive with a negative optical character, refractive index ranging from 1.762 to 1.770, strong dichroism showing blue and violet-blue from different angles.
Hardness & Durability
Origin Region
Notable sources include Kashmir, Myanmar (Burma), Sri Lanka (Ceylon), Madagascar, Australia, and Thailand. Forms in metamorphic and igneous rocks.
Hardness & Durability
Mohs hardness of 9 (second hardest naturally occurring mineral after diamond), excellent toughness, highly stable and resistant to heat and chemicals, making it exceptionally well-suited for everyday jewelry wear.
Care & Maintenance
Safe to clean with warm soapy water, ultrasonic cleaners, and steam cleaners unless heavily fractured. Store separately from softer stones to prevent scratching, though it is resistant to most household chemicals and sunlight.
Rarity & Value
Precious gemstone with rarity varying from common (commercially treated or lower grade) to extremely rare (fine untreated Kashmir or Burmese stones). Value depends intensely on color saturation, clarity, cut, and lack of thermal enhancement.
Special Characteristics
May exhibit asterism (star sapphire) if microscopic rutile needle inclusions are present in parallel orientations, though this polished tumbled specimen displays standard vitreous transparency and deep color saturation.
Lore & History
Historically revered as a stone of wisdom, royalty, prophecy, and divine favor. Ancient Persians believed the earth rested on a giant sapphire reflecting its blue color to the sky. Associated in modern crystal healing with the third eye and throat chakras, representing mental focus and spiritual clarity.