Hambergite
Hambergite · Collector Mineral / Rare Gemstone
Crystal System
Orthorhombic; typically occurs as prismatic crystals or bladed aggregates
Mineral Group
Borates
Chemical Formula
Be2(BO3)(OH)
Formation Process
Forms primarily in boron-rich granite pegmatites and occasionally in hydrothermal veins
About This Crystal
The specimen features vitreous to pearly, colorless to white bladed or prismatic crystals. It is translucent to transparent with visible cleavage planes and a characteristic flattened habit, often intergrown with reddish-brown matrix material.
Physical Characteristics
Color: Colorless, white, or pale yellowish; Streak: White; Cleavage: Perfect on {010}, good on {100}; Fracture: Uneven to subconchoidal; Specific Gravity: 2.33–2.37; Fluorescence: Usually inert but sometimes weak green under SWUV
Optical Properties
Biaxial positive; Refractive Index: 1.553–1.631; Birefringence: Extremely high (0.072); Dispersion: 0.017; No pleochroism in colorless specimens
Hardness & Durability
Origin Region
Notable sources include Madagascar (Anjanabonoina), Pakistan (Gilgit-Baltistan), and Norway (Langesundsfjord)
Hardness & Durability
Mohs hardness: 7.5; Toughness: Poor due to perfect cleavage; Stability: Stable under normal conditions but sensitive to mechanical shock
Care & Maintenance
Avoid ultrasonic cleaners and steam cleaning; clean with warm soapy water and a soft brush; store separately to prevent the cleavage planes from being impacted
Rarity & Value
Very rare; highly prized by mineral collectors; faceted gemstones are rare due to the difficulty of cutting crystals with perfect cleavage; value determined by transparency and crystal size
Special Characteristics
High birefringence is a key diagnostic feature, often causing a doubling of back facets when viewed through the crystal
Lore & History
Named in 1890 after Axel Hamberg; traditionally associated with clarity of thought and the crown chakra in metaphysical circles, though these lack scientific backing