Mining is expected to become a $1 billion industry in Nevada by 1985. That's the outlook from First Interstate Bank of Nevada, Reno, after noting the dramatic increase in the state's mineral output. Production rose to an all-time high of $391 million in 1980, a 55 percent gain from 1979. Nevada mines led all other states in the production of barite, magnesite, and mercury. Output of gold, along with gemstones, diatomite, and lithium minerals, ranks No. 2.
''Improvements in mining technology have made it possible to rework deposits that once were abandoned because they were not economically feasible,'' said bank researchers. ''Refinements in processing and recovery techniques'' have also helped, they said.