I tried looking around but couldn't find any sources attempting to answer this particular question. It's obviously impossible to know the exact answer, but all I'm looking for is an estimate. My best guess would be that it's about a tenth (or less) of the mass of the asteroid belt, with a composition roughly 10-15% metallic and 85-90% carbonaceous or silicate. Is anyone aware of any sources that attempt to give an estimate? If not, what would you say is a reasonable estimate?
Thanks in advance.