What is the luster of graphite?
metallic luster
Graphite is a soft, crystalline form of carbon. Other forms are diamond and fullerenes (“buckyballs”). It is gray to black, opaque, and has a metallic luster.
What mineral is Spessartine?
manganese aluminium garnet
Spessartine is a nesosilicate, manganese aluminium garnet species, Mn2+3Al2(SiO4)3. This mineral is sometimes mistakenly referred to as spessartite. Spessartine’s name is a derivative of Spessart in Bavaria, Germany, the type locality of the mineral….
| Spessartine | |
|---|---|
| Refractive index | 1.800 |
| Birefringence | none |
| Dispersion | Weak |
What type of mineral is graphite?
carbon
Pure graphite is a mineral form of the element carbon (element #6, symbol C). It forms as veins and disseminations in metamorphic rocks as the result of the metamorphism of organic material included in limestone deposits.
Is gypsum a cleavage or fracture?
| Gypsum | |
|---|---|
| Cleavage | Perfect on {010}, distinct on {100} |
| Fracture | Conchoidal on {100}, splintery parallel to [001] |
| Tenacity | Flexible, inelastic |
| Mohs scale hardness | 1.5–2 (defining mineral for 2) |
Does graphite have cleavage?
The carbon atoms in graphite are linked in a hexagonal network which forms sheets that are one atom thick. These sheets are poorly connected and easily cleave or slide over one another if subjected to a small amount of force. This gives graphite its very low hardness, its perfect cleavage, and its slippery feel.
What is the hardness of spessartine?
7
Spessartine/Hardness (Mohs hardness scale)
With a Mohs hardness of 7-7.5, its a durable gemstone. While some refer to the orange spessartines from Nambia as “mandarin garnets,” this is in fact a color range and not at true variety.
How is pyrolusite used?
Pyrolusite is used in the manufacture of steel and manganese bronze; in dry cells; and as a decolorizing agent in glass. For detailed physical properties, see oxide mineral (table).
Is graphite a stone or gem?
Graphite is a naturally occurring form of crystalline carbon. It is a native element mineral found in metamorphic and igneous rocks. Graphite is a mineral of extremes. It is extremely soft, cleaves with very light pressure, and has a very low specific gravity.
What is graphite good for?
Graphite is used in pencils and lubricants. It is a good conductor of heat and electricity. Its high conductivity makes it useful in electronic products such as electrodes, batteries, and solar panels.