Anyone know if a list exists that includes weights of PM gold coins including the weight of the capsule the coins are sold in?
That would be handy. But there is probably too much variation in capsule weight to make it accurate...
As a ROUGH guide, a 1oz silver Kookaburra in capsule weighs 38 grams, so allow ~7 grams for a capsule. 1oz of gold is smaller though, but I would be expecting a weight of ~37 grams in capsule. Haven't repeated the above measure with more accurate scales.
Forget weighing a coin in a capsule if you really want to check it. However if you have a lot of identical coins from the same source then maybe you can weigh one capsule then deduct this from the weights of others. Some capsules are thicker than others and some have protruding rims, adding weight. I just weighed a few Air-Tites and was surprised by the variation. If a capsule can add a few grams to a gold coin for example you will never know if it could be fake ( i.e. underweight ) Always remove the coin before weighing if in doubt. Also a good time to inspect the coin for condition, especially satisfying if viewing a proof with a 30x loupe in bright light. You can wear cotton gloves or finger cots to avoid fingermarks when handling. I use a photographic lens squirrel hair ( I think ) natural very soft brush for dusting if required.