Siderite is also the name of a type of iron meteorite.
Siderite is a mineral composed of iron(II) carbonate (FeCO3). It takes its name from the Greek word σίδηρος sideros, "iron". It is a valuable iron mineral, since it is 48% iron and contains no sulfur , magnesium commonly substitute for the iron resulting in the siderite-smithsonite , siderite-magnesite solid solution
Siderite has Mohs hardness of 3.75-4.25, a specific gravity of 3.96, a white streak or pearly luster. Siderite is antiferromagnetic of 37 K which can assist in its identification.
It crystallizes in the trigonal crystal system , and are rhombohedral in shape, typically with curved and striated faces. It also occurs in masses. Color ranges from yellow to dark brown or black, the latter being due to the presence of manganese.
Siderite is commonly found in hydrothermal veins, fluorite, and others. It is also a common diagenetic, where it sometimes forms concretions , which can encase three-dimensionally preserved fossils In sedimentary rocks , siderite commonly forms at shallow burial depths and its elemental composition is often related to the depositional environment of the enclosing sediments. In addition, a number of recent studies have used the oxygen isotopic composition of sphaerosiderite (a type associated with soils for the isotopic shortly after deposition.