We never had such (besides carat) here. And I'm glad, I don't have tabs of butter and tea at home, but only two half pound packets of butter and 1/4 pound of tea. (I know that tea taster use exactly 2.86 grams for atsing = the weight of a sixpence. Is there a special name for this as well?)
If a dummy or a child asked this question - they'd be answered - rightly or wrongly by now.