In the second paragraph it says: "For instance, one emerald mine established in 1981 in Santa Terezinha, Brazil, produced a peak of 25 tons of rough stones valued at $9 million in 1988; the same tonnage of stones mined in 2000 sold for only $898,000." If I took that sentence seriously, I would have to infer that the price dropped by an order of magnitude, presumably because other productive mines had been opened. But the preceding sentences says the contrary: "Thus high-quality gems can be mined out much faster than they are produced, essentially making them a finite resource." "The same tonnage" must be wrong. Please clarify.
posted by Joseph Fineman
February 20, 2012 @ 11:16 AM
In response to your question, the sentence means that the same weight in stones that were mined dropped in quality over the years, so was much less valuable by the last year cited.
posted by Fenella Saunders
February 20, 2012 @ 11:56 AM
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