Types of Minor Planets

It used to be easy - minor planets were either ``rocky'' or ``metallic''. That was before we took a good, close look. Here are some of the categories and sub-categories currently in use: (taken from J.F. Bell, et al., Asteroids II, R. Binzel, T. Gehrels, and M.S. Matthews, eds., Univ. of Arizona Press, 1989.)

Bell
Superclass
Tholen
Class
Inferred Minerals Analogous Meteorites
Primitive D organics + ? (ice??)(none)
P organics + ? (ice??)(none)
C clays, C, organicsCI,CM chondrites
K ol, pyx, carbon CV,CO chondrites
Q pyx, ol, gray NiFe H,L,LL chondrites ?
?Fe-free, pyx, gray NiFeEH,EL chondrites
Metamorphic T?highly altered C Cs ??
B + G + Fclays, opaquesHighly altered C Cs ?
Igneous Vplag, pyx, olbasaltic achondrites
Rol, pyxol-rich achondrites?
Spyx, ol, red NiFepallasites, lodranites, irons ?
Aolbrachinites
MNiFeirons
EFe-free pyxaubrites