Apophyllite
| Colour | White, Clear, Green, Blue |
|---|---|
| Mohs hardness | 4.5–5 |
| Lustre | Vitreous; pearly |
| Streak | White |
| Crystal system | Tetragonal |
| Transparency | Transparent to translucent |
| Cleavage | Perfect on (001) |
| Fracture | Uneven |
| Chemical formula | (K,Na)Ca 4 Si 8 O 20 (F,OH)·8H 2 O |
| Specific gravity | 2.3–2.4 |
What is Apophyllite?
The name apophyllite refers to a specific group of phyllosilicates, a class of minerals. Originally, the group name referred to a specific mineral, but was redefined in 1978 to stand for a class of minerals of similar chemical makeup that comprise a solid solution series, and includes the members fluorapophyllite-(K), fluorapophyllite-(Na), hydroxyapophyllite-(K). The name apophyllite is derived from the Greek apophyllízo, meaning 'it flakes off', a reference to this class's tendency to flake apart when heated, due to water loss. Exfoliation of apophyllite is also possible by treating it with
How to identify Apophyllite
- Lustre: Vitreous; pearly.
- Hardness: Mohs 4.5–5 — soft; a knife will scratch it.
- Streak: White.
- Habit: Tetragonal crystal system.
Apophyllite in different forms
Stones often confused with Apophyllite
Frequently asked questions
How hard is Apophyllite?
Apophyllite is Mohs 4.5–5 on the hardness scale.
What colour is Apophyllite?
Apophyllite is typically white, clear, green, blue (Usually white, colorless; also blue, green, brown, yellow, pink, violet).