| Kleinite | |
|---|---|
 Kleinite atop quartz from the McDermitt Mine | |
| General | |
| Category | Minerals |
| Formula | (Hg2N)(Cl,SO4) · nH2O |
| Strunz classification | 3.DD.35 |
| Crystal system | Hexagonal |
| Crystal class | Dihexagonal dipyramidal 6/mmm (6/m 2/m 2/m) |
| Unit cell | a = 6.762(2) Å, c = 11.068(3) Å, Z=4 |
| Identification | |
| Color | Light to canary-yellow, orange |
| Crystal habit | Short prismatic to equant crystals exhibiting prominent {1010}, {2021}, and {0001} |
| Cleavage | Uneven on {0001}, imperfect on {1010} |
| Tenacity | Brittle |
| Mohs scale hardness | 3.5 |
| Luster | Adamantine to greasy |
| Streak | Sulfur yellow |
| Diaphaneity | Transparent to translucent |
| Specific gravity | 7.9-8.0 |
| Optical properties | Uniaxial (+) (Biaxial below 130 °C (biaxial negative) and uniaxial above 130 °C (uniaxial positive). Isotropic above ~ 190 °C) |
| Refractive index | nω = 2.190 nε = 2.210 |
| Birefringence | δ = 0.020 |
| Other characteristics | Color deepens on exposure to daylight, original color returns in darkness |
| References | [1] [2] |
Kleinite is a rare mineral that has only been found in the United States and Germany that occurs in hydrothermal mercury deposits. [2] It occurs associated with calcite, gypsum and (rarely) barite or calomel. [3] Its color can range from pale yellow/canary yellow to orange, and it is transparent to translucent. [2] As a photosensitive mineral, its coloration darkens when exposed to light. [4]
Contents
It has been hypothesized that kleinite formed through a "reaction of cinnabar with oxidized meteoric water", with this reaction being the source of kleinite's nitrogen. [4]
