Daily Archives: March 23, 2011

PYROLUSITE [ Oxides and Hydroxides : Rutile ]

MnO2, manganese Oxide A major ore of manganese and as a mineral specimen Pyrolusite is the most common manganese mineral and is an important ore. Manganese is a strategically valuable metal since it is an essential ingredient in steel and other alloys. The mining term

COBALTITE [ Sulfides and Sulfosalts : Cobaltite ]

(Co, Fe)AsS, cobalt arsenic Sulfide Important ore of cobalt and as mineral specimens Cobaltite although rare is still an important and valuable ore of cobalt, a strategically and industrially useful metal. The symmetry of cobaltite is somewhat in dispute. Its structure is very similar to

SIDERITE [ Carbonates : Calcite ]

FeCO3, iron Carbonate A minor ore of iron and as mineral specimens Siderite is named for the Greek word for iron, sideros. The word siderite is used in a number of rarer minerals and except in the fact that they all contain iron, they are

MAGNETITE [ Oxides and Hydroxides : Spinel ]

Fe3O4, iron Oxide Major ore of iron and as mineral specimens Magnetite is a natural magnet, hence the name, giving it a very nice distinguishing characteristic. Explaining the magnetism is not easy but here is a go at it. Remember, electricity produces magnetic fields just

PYRITE [ Sulfides : Pyrite ]

FeS2, iron Sulfide A very minor ore of sulfur for sulfuric acid, used in jewellery under the trade name “marcasite” and as mineral specimens Pyrite is the classic “Fool’s Gold”. There are other shiny brassy yellow minerals, but pyrite is by far the most common