Heulandite
| Colour | White, Clear, Pink |
|---|---|
| Mohs hardness | 3.5–4 |
| Lustre | pearly, vitreous |
| Streak | white |
| Crystal system | Monoclinic More than one space group |
| Transparency | transparent to translucent |
| Cleavage | perfect basal |
| Chemical formula | {{chem2|(Na,Ca,K)_{5-6}[Al_{8-9}Si_{27-28}O72]*nH2O}} |
What is Heulandite?
Heulandite is the name of a series of tectosilicate minerals of the zeolite group. Prior to 1997, heulandite was recognized as a mineral species, but a reclassification in 1997 by the International Mineralogical Association changed it to a series name, with the mineral species being named:Heulandite-Ca Heulandite-Na Heulandite-K Heulandite-Sr Heulandite-Ba.
How to identify Heulandite
- Lustre: pearly, vitreous.
- Hardness: Mohs 3.5–4 — soft; a knife will scratch it.
- Streak: white.
- Habit: Monoclinic More than one space group crystal system.
Heulandite in different forms
Stones often confused with Heulandite
Frequently asked questions
How hard is Heulandite?
Heulandite is Mohs 3.5–4 on the hardness scale.
What colour is Heulandite?
Heulandite is typically white, clear, pink (colourless, yellow, green, white, pale pink).