Relative Abundance of Elements in the Universe

HHeONCFeSi
12000280016832.61
MgSNiAlCaNaCl
0.890.330.210.090.070.0450.025

(A. Cottrell, An Introduction to Metallurgy, 1975)

Elements upto iron can be created by fusion within stars, this requires temperatures of around 109 K, formation of heavier elements is unlikely because after a mass of about 56 the growth of the nucleus begins to absorb energy rather than release it. Heavier elements can be formed from the explosion of supernovae which throw out neutrons, protons and nuclei into space where they can meet other nuclei and unite with them.

Abundance of Elements in the Earths Crust (Weight %)

OSiAlFeCaNaK
49.225.677.504.713.392.632.40
MgHTiClPMnC
1.930.870.580.190.110.080.08

(A. Cottrell, An Introduction to Metallurgy, 1975)

The relative abundace of the elements in the earths crust is different because of the light elements being able to escape the earths gravity, and also material seperating on the basis of density between between the earths crust and the core.