Howardit-Scheibe HaH 285Classification of meteorites

 

Each meteorite coming to earth is unique and  differs regarding origin, construct, structure and mineral consistence both earthly rock and other meteorites. To bring order into the confusing variety of the world of meteorites, the early meteorite scientists in the beginning of the 19th century began to put meteorites into classes according to their most obvious features. According to the prevailing mineral consistences three main meteorite types were distinguished, the iron meteorites, the stony-iron meteorites and the stony meteorites.

Iron meteorites mainly consist of metal, a mixture of iron and nickel in different proportions. In them there also are found other elements and minerals in form of inclusions; however these rarely are more than 20% of the total mass. Stony meteorites at first sight resemble earthly stone and like it consists mainly of different silicates. They often contain finely distributed inclusions of nickel iron, but these normally are not more than 20% of the total mass. Stony iron meteorites are kind of a mixtype in which silicates and nickel-iron-minerals almost balance each other. All three main types were subdivided quite soon according to mineralogical viewpoints into further groups. This basic classification scheme was carried on till nowadays while meanwhile it is clear, that under various regards it is problematic. For example now one knows by means of modern chemistry and mineralogy, that stony meteorites are one heterogeneous class, into which quite indiscriminately stones were packed from planets, asteroids and burned out comets. On the other hand, one had to assess that many stony meteorites chemically were very familiar to certain iron meteorites, what suggests that they come from one and the same mother body.

Meteorite science is a science in radical

 

 

General classification of meteorites (overview):

 

Iron-meteorites

Octahedrites


Hexahedrites


Ataxites

 

 

Stony iron-meteorites

Pallasites


Mesosiderites


Further groups


Bencubbinites


Lodranites


Siderophyres

 

 

Stony-meteorites

Chondrites


Carbonaceous Chondrites (C-Chondrites)


CI-Chondrites


CM-Chondrites


CV-Chondrites


CO-Chondrites


CR-Chondrites


CK-Chondrites


CH-Chondrites


Ordinary Chondrites (H, L, LL-Chondrites)


H-Chondrites


L-Chondrites


LL-Chondrites


Enstatite Chondrites (E-Chondrites)


Rumuruti Chondrites (R-Chondrites)


Other Chondrites (K, F, B-Chondrite)


Kakangari Chondrites (K-Chondrites)


Forsterite Chondrites (F-Chondrites)


"Bencubbinites" (B-Chondrites)


Achondrites


PAC-Group (Primitive Achondrites)


Acapulcoites


Lodranites


Brachinites


Winonaites


Primitive Enstatite Achondrites (Zaklodzie, ITQIY)


Angrites


Aubrites


Ureilites


HED-Group ("Vestameteorites")


Diogenites


Eucrites


Howardites


LUN-Group ("Moonmeteorites")


Anorthositical Regolith-Highlandbreccias


Fragmental Highlandbreccias


Impact-melt Breccias


Marebasalts


Maregabbros


SNC-Group ("Marsmeteorites")


Shergottites


Nakhlites


Chassignites


Orthopyroxenites

 

 

Frequency of individual types of meteorites:*

 

Meteorite type

Falls

Finds

Total number

Iron-meteorites

48

817

865

Stony-iron meteorites

12

104

116

Stony-meteorites

940

20.574

21.514

Total number

1.000

21.495

22.495

 

*Considered were all finds and falls until dec. 1999 (after Grady, Monica M. : Catalogue of meteorite)

 

You find more detailed information about the classification of the single meteorite types and the accompanying groups under the categories Iron-meteorites, Stony-iron-meteorites and Stony-meteorites.

See also: INSTITUT FÜR PLANETOLOGIE