Rhodonite
Rhodonite (Manganese Silicate) · Semi-Precious Gemstone / Decorative Stone
Crystal System
Triclinic; typically found in massive or granular habits in finished lapidary pieces
Mineral Group
Silicates; Inosilicates (Pyroxenoid group)
Chemical Formula
(Mn,Fe,Mg,Ca)SiO3
Formation Process
Metamorphic and hydrothermal; typically forms in manganese-rich sedimentary rocks subjected to regional or contact metamorphism
About This Crystal
An opaque pink to rose-red stone characterized by distinctive black dendritic inclusions or veins of manganese oxide. It features a vitreous to pearly luster when polished.
Physical Characteristics
Color: Pink to brownish-red with black veins; Streak: White; Cleavage: Perfect in two directions; Fracture: Conchoidal to uneven; Specific Gravity: 3.5–3.7; Fluorescence: Usually none, though some specimens show weak dark red.
Optical Properties
Refractive Index: 1.716–1.752; Birefringence: 0.010–0.015; Pleochroism: Weak (red-pink to yellow-red); Non-phenomenal in massive form.
Hardness & Durability
Origin Region
Russia (Urals), Australia, Brazil, Peru, and USA (New Jersey and Massachusetts)
Hardness & Durability
Mohs Hardness: 5.5–6.5; Brittle toughness; sensitive to sudden temperature changes and strong acids; reasonable jewelry durability for pendants/earrings.
Care & Maintenance
Clean with warm soapy water and a soft cloth; avoid ultrasonic or steam cleaners. Store away from harder stones like quartz or topaz to prevent scratching.
Rarity & Value
Relatively common; value is determined by the intensity of the pink color and the aesthetic pattern of the black manganese veins. Higher purity pink is rarer.
Special Characteristics
Known for its contrasting 'matrix' patterns where black manganese oxide (like pyrolusite) creates spider-web or dendritic textures against the pink base.
Lore & History
Historically used in Russia as a protective stone and for decorative architecture (e.g., the Moscow Metro). In lore, it is known as the 'Stone of Compassion' and associated with the Heart Chakra.