Jacobsite
Jacobsite is named after its discovery locality, at the Jakobsberg mine, near Stockholm, Värmland, Sweden.
Jacobsite forms opaque to translucent, black to brownish black crystals or coarse to fine granular masses with metallic to submetallic lustre.
Jacobsite forms opaque to translucent, black to brownish black crystals or coarse to fine granular masses with metallic to submetallic lustre.
| General Information | ||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chemical Formula |
| |||||||||||||||||||||||||
| Physical Properties of Jacobsite | ||||||||||||||||||||||||||
| Mohs Hardness | 5.5 to 6.5, Handbook of mineralogy (2001) | |||||||||||||||||||||||||
| Specific Gravity | 4.76 to 5.03, Handbook of mineralogy (2001) | |||||||||||||||||||||||||
| Optical Properties of Jacobsite | ||||||||||||||||||||||||||
| Optical Character | Isotropic, Handbook of mineralogy (2001) | |||||||||||||||||||||||||
| Colour | ||||||||||||||||||||||||||
| Colour (General) | Black to brownish black; grayish white with olive tint in reflected light, with brown internal reflections., Handbook of mineralogy (2001) | |||||||||||||||||||||||||
| Transparency | Translucent,Opaque, Handbook of mineralogy (2001) Opaque, translucent on thin edges | |||||||||||||||||||||||||
| Lustre | Dull (Earthy),Metallic,Submetallic, Handbook of mineralogy (2001) Metallic, splendent to semimetallic, dull | |||||||||||||||||||||||||
| Crystallography of Jacobsite | ||||||||||||||||||||||||||
| Crystal System | Isometric, Handbook of mineralogy (2001) | |||||||||||||||||||||||||
| Habit | Rarely in octahedral crystals, to 4 mm, which may exhibit exsolved hausmannite or galaxite; coarse to fine granular, massive., Handbook of mineralogy (2001) | |||||||||||||||||||||||||
| Geological Environment | ||||||||||||||||||||||||||
| Where found: | A primary mineral or an alteration product of other manganese-bearing minerals in some metamorphosed manganese deposits., Handbook of mineralogy (2001) | |||||||||||||||||||||||||
| Further Information | ||||||||||||||||||||||||||
| Mineral information: | Jacobsite information at mindat.org | |||||||||||||||||||||||||