Caesium-137 has a number of practical uses. In small amounts, it is used to calibrate radiation-detection equipment. In medicine, it is used in radiation therapy. In industry, it is used in flow meters, thickness gauges, moisture-density gauges (For density readings,Americium-241/Beryillium providing the moisture reading and in gamma ray well logging devices.Caesium-137 is not widely used for industrial radiography because it is quite chemically reactive, and hence, difficult to handle. The salts of caesium are also soluble in water, and this complicates the safe handling of caesium. Cobalt-60, 60
27Co, is preferred for radiography, since it is chemically a rather nonreactive metal offering higher energy gamma-ray photons. As a man-made isotope it has been used to date wine and detect counterfeits and as a relative-dating material for assessing the age of sedimentation occurring after 1954.