| Mineral | MILLERITE |
| Chemistry | NiS |
| Class | Sulfides and Sulfosalts |
| Uses | Mineral specimens and as a very minor ore of nickel. |
| Color | Pale brass-Yellow with an iridescent tarnishand Greenish -grey. |
| Luster | Metallic |
| Transparency | Crystals are opaque. |
| CrystalSystem | Trigonal |
| CrystalHabits | include aggregates of acicular (hair-like) or capillary crystals.The aggregates form radial sprays or randomly dispersed individual hairs.Also seen as fibrous coatings and rarely found in granular masses.Millerite is one of several minerals that is found in iron-nickel meteorites. |
| Cleavage | Perfect Perfect on {10-11} and {01-12}. |
| Fracture | perfect in several directions but is rarely discernible due to the extremely thin crystals. |
| Hardness | 3 - 3½ |
| SpecificGravity | 5.37 g/ccm |
| Streak | Greenish black. |
| AssociatedMinerals | A low-temperature mineral which occurs in sulfidic limestones and dolostonesand as a late-forming mineral in nickel sulfide deposits. |
| Characteristics | may tarnish to a gray color and crystals can be attacked by acids. |
| Occurences | include south central Indiana, Keokuk, Iowa, Gap Mine, Pennsylvania and Sterling Mine, New York, USA; Freiberg, Germany; Glamorgan, Wales, England and Sherbrooke and Planet Mines, Quebec. |
| Indicators | crystal habit, associations and environment, color and luster. |
| IMAStatus | Approved |
| Discovered | 1845 |
| CellParameters | a = 9.62c = 3.149 |
| Ratio | a:c = 1 : 0.327 |
| TypeLocality | Jáchymov ( St Joachimsthal) Ostrov Krusné Hory Mts ( Erzgebirge) Karlovy Vary Region Bohemia Czech Republic |
| Strunz | 2/C.21-30 2 : Sulphides C : Sulphides with metal: sulphurselenium and tellurium = 1:1 21 : Millerite series |
