Specific gravity of any material is defined as the ratio of weight of a volume of a material to the weight of same volume of water at particular temperature. So in this test the quantities are very important. Water is not used in testing of specific gravity of cement because cement reacts with water and form compounds. Thus , the quantities measured prior to the commencement of test will not be same after the test. Therefore kerosene which is inert (non-reactive) with cement is used. We should observe here that we calculate the specific gravity of cement with respect to kerosene and convert it with respect to water by using 0.79 (specific gravity of kerosene) in the formula of the same.

**Craig Mason**

Engineering Manager