meteorite classification

meteorite type	stony			stony-iron		iron
composition	mostly silicates with up to 15% Fe/Ni			silicates and Fe/Ni in roughly equal amounts; generally olivine and pyroxene embedded in Fe/Ni matrix		nearly entirely Fe (80-90%) and Ni (10-20)%
	achondrites (10%) (contain no chondrules)	chondrites (90%) (contain chondrules)
		ordinary chondritles	carbonaceous chondrites (contain significant carbon and often amino acids)	pallasites	mesosiderites
frequency of falls	8%	60%	26%	1%		5%

asteroid class			C type	S type		M type

origin/formation	surface of parent body	heated by impact on surface of parent body	aggregates of the most primitive solar system materials (the non-volatile composition matches that of the sun)	mantle-core boundary of parent body that differentiated	collision of two different bodies aggregate of crust and mantle of the bodies	core of parent body that differentiated
examples		Gao Guenie (3/5/60, Burkina Faso)	Allende (2/8/69, Mexico) contains microscopic diamond with non-solar-system isotopic abundances; likely a product of a nearby supernova	Imilac (found 1922, Atacama, Chile)		Canyon Diablo (30,000 yrs ago, Meteor Crater, Arizona)
			Murchison (9/28/69, Australia) contains LH and Rh amino acids, including 12 not occurring in terrestrial life			Odessa (50,000 yrs ago, found 1922, Texas)
						Gibeon (found 1836, Namibia)
						Sikhote-Alin (2/12/47, Siberia)
						Zagora (found 1987, Morocco) iron, with silicate inclusions