Dear Ivy, All precious metals weights are measured in troy ounces in
the USA. Avoirdupois weight is based on a pound weighting 16 ounces
(7,000 grains). In troy weight the pound is 12 ounces (5,760 grains)
or 240 pennyweights. Both weight systems utilize grains however the
pound weight is the big difference.
Cathy Wheless
www.cathywheless.com
@Cathy_Wheless