MANGANESE, AOETATE OF, may be obtained in a pure state by crystallization from a strong solution of carbonate of manganese (diagolite) in aoetio acid. The crystals are stable in the air at ordinary temperatures, soluble in three times their weight of cold water, and in alcohol. Upon a large scale the salt is prepared by mixing solutions of sulphate of manganese and acetate of lime or lead; sulphate of lime or lead precipitates, and, after settling, the clear acetate of manganese iu solution is drawn off. The reaction is by no means a strong ono, and the mixture must, therefore, be well agitated to ensure decomposition of the manganese salt. The use of acetate of lead is to be preferred, although the process is more costly than when a lime salt is employed. The best proportions are 4 parts of sulphate of manganese, 3i of water, and 7 of good brown acetate of lead.
The crystals shettlil be iu the form of pale rose-coloured splinters or small prisms.
Acetate of manganese is used HS a substitute for bronze liquor (muriate of mang,anese) by dyers and calico-printers. Tho latter is the cheaper article, but the acetate is to be preferred, as it does not contain the same excess of free acid, whereby the cloth is injured. From these salts the colour known as " manganese brown " te. obtained by impregnating the cloth with them and passing in lime or soda ash. Oxide of manganese (the protoxide) is precipitated upon the cloth and subjected to the oxidizing agency of the air, or, usually, the cloth is passed through a bath of chloride of lime. The manufacture is only carried on to a limited extent in Lancashire and other calico printing and dyeing districts. Acetate of manganese is also used in medicine.