Question

what is the main difference between roasting and calcinations

Answer 1

in roasting sulphide containing ores are converted into metal and in calcination carbonate containing ore are converted into metal
roasting is done in presence is oxygen
calcination is done in absence is of oxygen

Answer 2

Roasting is pyrochemical process in which the ore is heated in the presence of oxygen or air is below its melting point.
Authorities differ on the calcination.