Silicon in carbonaceous chondrite metal: relic of high-temperature condensation

Science. 1979 Oct 26;206(4417):449-51. doi: 10.1126/science.206.4417.449.

Abstract

Electron microprobe analyses of an extraordinarily large metal grain from the Murchison type 2 carbonaceous chondrite gave 0.24 mole percent silicon. Thermodynamic calculations show that this is a natural consequence of condensation of alloys from the solar nebular gas at a total pressure l0(-5) less, similar P(tot) < l0(-3) atmosphere, provided they failed to equilibrate with it after cooling to < 1200 kelvins.