On April 17, 2021, the Loadstone Mining Company purchased the rights to a coal mine. The purchase price plus additional costs necessary to prepare the mine for extraction of the coal totaled $4,500,000. The company expects to extract 900,000 tons of coal during a four-year period. During 2021, 240,000 tons were extracted and sold immediately.

Required:
1. Calculate depletion for 2021.
2. Is depletion considered part of the product cost and included in the cost of inventory (yes/no)? Discuss.