The chemistry, oil yields, and geology of eastern oil shales are quite different from western ones, so are the mechanical properties. A primary variable of the mechanical properties is the specific gravity of the rock which is related to oil yield. Saturation, buoyancy and other techniques are used to accurately determine the specific gravity. Fischer assay is used to establish the oil yield. Based on 30 samples tested, with specific gravity ranges from 2.14 to 2.27 and oil yield from 18 to 12 gallons/ton respectively, a reliable liner equation is derived with high correlation coefficient (about 0.9).