Difference b/w rroasting and calcination

roasting is the process of heating ores  in presence of excess air it is process use for only sulphide ores for eg
zns + o2-zno +so2

calcination is process of heating carbonate ores in presence of limited air for eg
ZnCo3 +O2-Zno+Co2

Rosting is the process in which the ore is heated below its melting point in presence of air to oxidise the impurities. while Calcination is the process if heating the ore below its melting point in absence of air to remove volatile impurities like arsenic etc

Heating a metal ore in presence of oxygen to convert it into metal oxide is roasting. Sulphide ores are roasted. Eg. zinc blende (zinc sulphide)
Heating of metal ore in absence of oxygen to convert it into metal oxide is calcination. Carbonate ores are calcinated. eg. calamine (zinc carbonate)

Roasting is a process in metallurgy in which a sulfide ore is heated in air. The process may convert a metal sulfide to a metal oxide or to a free metal. Example: Roasting ZnS may yield ZnO; roasting HgS may yield free Hg metal Calcination. ... The IUPAC defines calcination as "heating to high temperatures in air or oxygen". However, calcination is also used to mean a thermal treatment process in the absence or limited supply of air or oxygen applied to ores and other solid materials to bring about a thermal decomposition.

ROASTING IS DONE IN PRESENCE OF AIR AND CALCINATION IS DONE IN ABSENCE OF AIR