Rhodonite
Rhodonite (Manganese Silicate) · Semi-Precious Gemstone / Decorative Stone
Crystal System
Triclinic; typically found in massive, granular, or compact habits rather than distinct crystals.
Mineral Group
Silicates (Inosilicates) - Pyroxenoid group
Chemical Formula
(Mn,Fe,Mg,Ca)SiO3
Formation Process
Metamorphic, typically forming in manganese-rich environments through regional or contact metamorphism of manganese ores.
About This Crystal
Tumbled stone with a rose-pink to deep red body color, featuring characteristic black dendritic inclusions of manganese oxide. It is translucent to opaque with a vitreous to pearly luster.
Physical Characteristics
Color: Pink to brownish-red; Streak: White; Cleavage: Perfect in two directions (but rarely seen in massive forms); Fracture: Uneven to conchoidal; Specific Gravity: 3.5–3.7; Fluorescence: Usually none, though some specimens may show weak red.
Optical Properties
Refractive Index: 1.716–1.752; Birefringence: 0.010–0.015; Pleochroism: Weak (red-pink to yellow-red); Non-phenomenal in this tumbled state.
Hardness & Durability
Origin Region
Prominent sources include Russia (Ural Mountains), Australia (Broken Hill), Brazil, Peru, Madagascar, and the USA (New Jersey).
Hardness & Durability
Mohs hardness: 5.5–6.5. Toughness is generally good due to its compact structure, though it can be brittle along cleavage planes.
Care & Maintenance
Clean with warm soapy water and a soft brush; avoid ultrasonic cleaners, steam, and harsh acids which can damage the manganese oxides. Store separately to prevent scratching.
Rarity & Value
Common globally, but high-quality translucent specimens or 'imperial' rhodonite are rare. Value is determined by the balance of pink versus black oxide patterns.
Special Characteristics
Known for its 'black vein' patterns caused by manganese oxide oxidation. Occasionally exhibits a glassy transparency in rare gem-quality crystal forms.
Lore & History
Historically used in Russia for decorative architecture and jewelry (notably by Fabergé). Traditionally associated with the Heart Chakra and viewed as a stone of compassion and emotional healing.