Dravite is the brown, Mg-rich tourmaline variety of tourmaline. It is less common than the other varieties and commonly forms in crystalline limestones.
| (Na,Ca)(Li,Mg,Al)3(Al,Fe,Mn)6(BO3)3(Si6O18)(OH)4 |
|
| Cyclosilicate |
|
| Hexagonal |
|
| 3m |
|
| 7-7.5 |
|
| 3.0-3.25 |
|
| {1011} indistinct |
|
| Sub-conchoidal |
|
| Brown |
|
| White |
|
| Vitreous, resinous |
|
| Transparent/translucent |
|
| Prismatic |
|
| Piezoelectric |
|
| Notable Localities: |
New York; Australia |
| Uses: |
Manufacture of pressure gauges |
Specimens:
| |
|
