Thulite
What is Thulite?
Thulite is a pink variety of the mineral zoisite and is often found in Norway, Australia, and the United States. It’s primarily used as a gemstone and is popular for its rosy pink color.
Thulite is a unique gemstone that comes in shades of rosy pink. Its vibrant hue and unique appearance make it a popular choice for jewelry and decorative items, especially beads and pendants.
| Chemical Classification | Inorganic - Silicate (Zoisite) |
| Color | Thulite is typically pink to reddish, often intergrown with white calcite or other minerals. |
| Streak | White |
| Luster | Vitreous to pearly. |
| Transparency | Opaque. |
| Occurrence | Norway (where it was first discovered), the United States, and Australia. |
| Formation | Thulite forms in metamorphic rocks and is often found in massive form rather than crystals. |
| Diaphaneity | Opaque |
| Cleavage | Perfect in two directions |
| Mohs Hardness | 6 to 7. |
| Specific Gravity | 3.10 to 3.38. |
| Diagnostic Properties | Pink, a variety of zoisite. |
| Chemical Composition | Ca2Al3(SiO4)(Si2O7)O(OH) |
| Pleochroism | Weak. |
| Crystal System | Triclinic (variety of Zoisite) |
| Optical Properties | Biaxial (+) |
| Refractive Index | Varies due to mixture of minerals |
| Birefringence | 0.006 - 0.013 |
| 2V angle | Measured: 78° to 82° |
| Dispersion | Not notably high. |