Description
Rhodonite
- rhodonite (ROE-duh-nite) is a mineral species; triclinic crystal system;chemical composition (Mn, Fe, Mg, Ca)SiO3
- usually translucent to opaque pink to brownish or purplish red, often with black veins or splotches (may also have greenish or yellowish areas due to impurities); also transparent pink to red (rare)
Identification
- Optic Character: DR, biaxial positive; AGG
- Refractive Index: 1.733-1.747 (+.010, -.013); spot reading usually 1.73, but may be 1.54 due to quartz impurities
- Birefringence: .010 to .014
- Pleochroism: none in aggregate material; transparent crystals – weak to moderate, orange-red and brownish red
- Ultraviolet Fluorescence: inert
- Absorption Spectra: broad band centered around 545 nm and a line at 503 nm
- Cause of Color: manganese
- Specific Gravity: 3.50 (+.26, -.20)
- Polish Luster: vitreous to subvitreous
- Fracture: conchoidal to uneven or granular
Luster: dull to vitreous - Cleavage: perfect in two directions but usually obscured by aggregate structure
- Identifying Characteristics: black veins or spots of manganese oxide
- Crystal Habit: usually massive
- Hardness: 5 1/2 to 6 1/2
- Toughness: good (aggregates) to poor (transparent stones)
Sources: Australia, Brazil, Germany, Italy, Mexico, Romania, Sweden, US, USSR
Stone information is reference from
Gem Reference Guide, Published by GIA. ISBN 0-87311-019-6
Gemstones of the World, Published by Sterling Publishing Co., Inc NY, ISBN 1-4027-4016-6
Encyclopedia of GEMSTONE, Published by ISHINSHA CO., LTD. ISBN 978-986-251-831-1
