This paper focuses on a preliminary study of the typical inherent variabilities in the basic properties of intact rocks. Results are presented of an extensive literature review on inherent variability, which can be modeled as a random field that is described concisely by the coefficient of variation (COV) and the scale of fluctuation. Only the COV is discussed herein. The COV. of inherent variability for various test measurements is given in histograms to illustrate its population distribution. The means and standard deviations of the COV are shown with the total number of data groups, and the shapes of the histograms are discussed. The effects of sample size, moisture content, and weathering also are discussed where possible.