MANGANESE.
Mung-kin, . . . Braunatoin,Glaasoiae, GER. Bruinstein, . . . D UT. Kohn ka pathar, . limp. Savon du verro, . . Fit. Iddali kalu, . . TEL.
The substance known in commerce under this name is the peroxide or black oxide of the metal. It is commonly of an earthy appearance, and mixed with other ingredients, but sometimes in crystals of a black colour and metallic lustre. The sub stance is well suited for glazing pottery, along with galena and felspar. In small quantities it gives a yellow colour ; in large, brown ; then a blood-red, •purple, or black, as the proportion of manganese is increased. It has also the property of hardening the glaze, so as to resist vinegar and weak acids. Concentrated mineral acids, however, will corrode it. It is largely con sumed in the manufacture of bleaching compounds; it is also used by potters ; and it is considered the cheapest material from which to procure oxygen.
At the Madras Exhibitions of 1855 and 1857, the silicated sesquioxide was exhibited front Vizian agram in blocks, weighing from 2 to 3 cwt. each, with from 53 to 54 per cent. of metallic mangan
ese. It has been discovered in a good many parts of the Madras Presidency under the form of earthy manganese ore, dendritic manganese ore, and com bined with iron in a good many of the ochrey iron stones, laterites, claystones, and cotton soils of India. It was mined by Hyder Ali and Tipu Sultan in the Kupputgode range. It has been found also in the iron ore near the lake at Ootacarnund, and in the Kaiti valley ; also in Mergui, Burma, and the Himalaya.
Good ore occurs in Kurnool, at Tumkur in Mysore ; in Sundur and Rndmr in the Coileinitlah taluk. Brown wad and brown fibrous manganese occur at the Red Hills, Bangalore, and Cuddapah.
In the bazars of the Panjab, manganese in the forms of a silicated sesquioxido and a peroxide is obtainable as a black powder, or in lumps of the pyrolusite.
Manganese is found in China in connection with the iron ores of Chin-Chan of Ho-nan.—Smith ; M. E. J. R.; TVaterstone; Faulkner; Powell, Hand book; Mason's Tenasserim.