| The investigation includes six bulk samples of magnesite from Salem, Mysore,
Ajmer and Almora to represent a comprehensive account of the indigenous resources.
They comtitute two distinct types: cryptocrystalline and crystalline. The different
deposits have been outlined comparatively in their modes of occurrence and origin.
Mineralogical data include petrography, dta and x-ray analysis; they are in close
correspondence with the chemical compositions of the different samples. Studies
on sintering at temjJCratures between 1500° and I700°C indicate that the Indian
magnesites can be properly dead-burnt around 1650°C. Girechchina magnesite
containing about 35% dolomite may be calcined inert at about 1550°C. The segregation
of matrix, and the role of iron and other impurities during calcination have
been discussed. Magnesite and chrome-magnesite refractories made from each
type have been found to develop satisfactory properties, in gener.al, and particularly
with respect to refractorieness underload, and volume stability at I700°C.
Dicalcium silicate bonded refractories from Girechchina magnesite indicate higher
refractoriness underload and cold crushing strength. |
