Problem: A copper-gold-silver ore assays: 0.38 oz/ton Au, 4.20 oz/ton Ag, 2.5% Cu as revenue metals, without any significant penalty elements. This ore can either be shipped directly to a smelter for treatment or processed in a concentrator and the concentrate be shipped to the smelter. In the concentrator, 100 tons of 1.0.m. ore yields 9.00 tons of concentrate. The concentrate assays: 4.20 oz/ton Au, 45.00 oz/ton Ag, and 24.5% Cu as payable metals. The r.o.m. ore or the concentrate is shipped to a copper smelter which pays for the metals according to the following simplified smelter schedule: Gold payment: If the ore/concentrate contains more than 0.03 oz Au per dry ton, pay for 96.75% of gold at LME price* Silver payment: If the ore/concentrate contains more than 1.0 oz Ag per dry ton, pay for 95% of silver at LME price*, after a deduction of 1 oz of silver per ton treated Copper payment: Deduct from the copper assay 1.3%, pay for the rest at LME price* Smelter charge (TC) $100 per ton of ore. Refining charge (RC) $ 0.15 per kg of payable copper. *Use October 22, 2021 London Metal Exchange (LME) prices. Freight cost: $ 20 per ton from mine to smelter. Mining cost: $ 15 per ton. Mineral processing (milling) cost: $ 20 per ton ore processed Calculate the NSR (per-ton-shipped-to-smelter basis) and the overall return per ton ore basis for two cases: Case I: Direct shipment of the ore to the smelter, Case II: Processing the ore and shipping the concentrate to the smelter. Compare and discuss your results. *** All tons in the problem are meant to be metric tons. (1 metric ton = 2200 lbs) ***1 ounce(oz.) = 31.10 grams