sandwich baggies vary a lot...i've measured them in at anywhere from 0.5 to 1.4 grams for the standard, 'lick' baggies and the ziplock sandwich size usually runs around 5 grams with the large 'pounders' coming in around 9 to 11 grams...but they too vary according to brand.

but the "baggie" name-brand ones seem to be fairly consistant at close to 1.0 g's...