Salter Mining Company purchased the Northern Tier Mine for $52 million cash. The mine was estimated to contain 8.1 million tons of ore and to have a residual value of $7.3 million. During the first year of mining operations at the Northern Tier Mine, 90,000 tons of ore were mined, of which 18,000 tons were sold.

a. Prepare a journal entry to record depletion during the year.