In general the, most common thickeners in lubricating greases are soaps of alkaline earth metals such as calcium, sodium, lithium etc. However, there are some non soap thickeners used for making greases. The most common amongst them are organophilic clays, polyurea, silica, graphite etc. Clay base greases have very high drop point and are used for high temperature applications in various industries such as steel plants, cement plants etc. Polyurea greases are popular for high temperature applications and long life.