Muscovite mica surfaces were studied with X-ray photoelectron spectros
copy. The air-cleaved mica surfaces showed a large Cis peak in the ran
ge 285.3-285.9 eV indicating the presence of carbon species other than
the adventitious. Normal emission and grazing emission spectra were u
tilised to calculate bulk and surface elemental ratios respectively fo
r air-cleaved as well as vacuum-cleaved mica surfaces. Preferential at
tenuation of some peaks has been proposed for a few abnormal elemental
ratios. Apparent shifts in binding energy due to sample charging were
investigated for differently treated mica surfaces. Changes in the ap
parent shift are shown to be due to the existence of strong dipole fie
lds at the surface resulting in a potential drop of as much as 3.6V ac
ross the dipole layer.