Which weighs more, gold or feathers?

Shouldn't we address this one to Helen?

I should check, but as I recall Troy ounces are bigger but there are only 12 to a pound, which makes gold-by-the-ounce heavier than feathers-by-the-ounce, but gold-by-the-pound-(Troy) is lighter than feathers-by-the-pound-(avoirdupois). Is this a good argument for using metric system, or what? Gold-and-feathers-by-the-gram(me) weigh exactly the same!

Edit: Yes. A Troy ounce is bigger, but an avoirdupois pound is bigger. The conversion is

one ounce Troy = 480 grains
one ounce avdp = 437.5 grains and

one pound Troy = 5760 grains
one pound avdp = 7000 grains

from http://www.homeoint.org/cazalet/weight/ and any number of other sources

P.S. I note that they are all given in Troy grains !