Abundance of the Elements in the Earth's Crust

The abundances of the elements in the earth's crust vary widely and so a logarithmic scale is used. We report the unitless quantity

(milligrams of the element in earth's crust )
log   --------------------------------------------------------
(kilograms of crustal material )

These values are estimates, since there is wide variability in the distribution of the elements and not all of the concentrated deposits of any given element may have been discovered.

Values were obtained from P.A. Cox, THE ELEMENTS - THEIR ORIGIN, ABUNDANCE, AND DISTRIBUTION, Oxford, Oxford University Press, 1989, page 182.