Over the last couple of days, the “List of strange units of measurement” at Wikipedia has provided me with a lot of pleasure.

A hybrid standard quantity used in mining is the assay ton (AT), which is as many milligrams as there are Troy ounces in an avoirdupois long ton. So to find how many ounces of gold are in a ton of rock, one measures the number of milligrams of gold in an assay ton of rock.

As has the last sentence in this newspaper article:

Running of the Elephants.