Gold films have been shown to oxidize upon exposure to UV light in air (UV/ozone cleaning) [H. Ron and I. Rubenstein, Langmuir 10, 4566 (1994)].  UV exposed gold substrates incubated in solutions of long chain alkanethiol show islands on the monolayer surface when imaged with non-contact atomic force microscopy (AFM).  Islands are observed on substrates exposed to solutions of octadecane-, hexadecane-, and dodecanethiol at 1.0-0.01 mM concentrations in ethanol and hexadecane. The height of the islands above the monolayer is approximately twice the height of the alkanethiol monolayer and the diameter is 20-200 nm. Islands are easily pushed aside during contact mode AFM imaging without damaging the underlying monolayer. AFM on samples with submonolayer coverage shows that the islands do not develop until the late stages of monolayer formation.  Islands are not observed on freshly prepared substrates or on UV exposed substrates that are reduced by soaking in ethanol prior incubation.