Phosphate Mineral
Vivianite – Crystal Wiki
Sensitive and Fascinating – Characteristic Blue-Green Hues from Oxidation
Vivianite (Fe3(PO4)2·8H2O)
Properties & Characteristics
Scientific Data
- Chemical Formula
- Fe3(PO4)2·8H2O
- Crystal System
- Monoclinic
- Mohs Hardness
- 1.5–2
- Density
- 2.6–2.7 g/cm3
Physical Properties
- Color
- Pale to blue-green, often darkening
- Luster
- Vitreous to pearly
- Transparency
- Transparent to translucent
- Special Feature
- Significant color change with exposure to air and light
What is Vivianite?
Vivianite is a hydrous iron phosphate with a distinct color change from pale to blue-green.
Formation
It forms in reducing, moist environments with phosphate and iron sources.
Locations & Market
Known occurrences include Bolivia, Russia, and Germany. High-quality crystals are sought after but delicate.
Quality Characteristics
Essential factors are crystal form, depth of color, and undamaged condition.
Care & Handling
Store in low light, dry conditions, and protected from impact; touch as little as possible.
Frequently Asked Questions
Why does Vivianite darken?
Due to oxidation processes of iron within the mineral lattice.
Is Vivianite suitable for jewelry?
Generally no, as it is very soft and delicate.
How do I store Vivianite correctly?
In low light and dry conditions, preferably in a protected display case environment.