[Harmless Teddy Bear]

However the troy ounce is based on the Roman weight system where a troy ounce equaled a unit called a "uncia" which was 1/12 of a "aes grave" (troy pound). That system of weights dates to at least 289 BC.

I have no idea where the Romans got it from but it probably was based on something older yet.

[TheOldLady]

I love you guys and FR. Thank you. I’m never too old to learn, or perhaps relearn something I forgot.

High school, 48 years ago. ;-D