If 16,000 tons of ore are processed at the imperial topaz mine, approximately how many pounds of topaz would be recovered?

• A. 66 pounds
• B. 264 pounds
• C. 132 pounds
• D. 33 pounds

Answer: (C)

Converting the ore weight to pounds and applying a very small gemstone concentration shows why a result in the low hundreds of pounds makes sense here. If 16,000 tons of ore are processed, that’s 16,000 × 2,000 = 32,000,000 pounds of ore. Topaz in ore is present only at a tiny fraction, often measured in parts per million. Using an approximate concentration of a few parts per million gives you a recovered amount on the order of a hundred pounds.

For example, 32,000,000 pounds × 4 × 10^-6 equals about 128 pounds, which aligns with the 132-pound option when rounded. So the best estimate is about 132 pounds of topaz recovered from that tonnage, reflecting how small the gemstone yield is relative to the total ore mass. The exact figure depends on the ore’s grade and recovery efficiency, but the magnitude—hundreds of pounds at this scale—fits the scenario.