Let's not forget that "dross" takes us back to Homer Pound's work assaying silver and gold in the Philadelphia Mint. Ezra recalled the different processes with remarkable precision in print and out-loud many times, including in the Donald Hall interview (a history of the Mint from the time of Homer's employment details the procedures and mentions Homer as well). Anyone who orders my dissertation should beware that I got this wrong when I said Pound got it wrong. The crucible used in the gold refining process used by Homer does indeed absorb impurities, so that the pure gold does indeed remain. Jonathan Gill Columbia University