Thulite
Variety Ca2Al3(SiO4)(Si2O7)O(OH)
About it
Massive pink zoisite coloured by manganese, often mottled with white calcite or quartz. Named for Thule, an old name for Norway, where it was first found and is still best known.
- Type
- Variety
- Group
- Zoisite variety (epidote group)
- Formula
- Ca2Al3(SiO4)(Si2O7)O(OH)
- Hardness (Mohs)
- 6–6.5
- Specific gravity
- 3.1–3.38
- Streak
- white
- Lustre
- vitreous (glassy), pearly
- Crystal system
- Orthorhombic
- Colours
- pink, rose red, often with white
- Transparency
- translucent, opaque
- Cleavage and fracture
- perfect in one direction; uneven to conchoidal fracture
Typical values: real specimens vary. For more, see mindat.org.