What are your thoughts on the 2 x serial 8 ????????
Mightn't be a serial number. Could be a batch number or something like that, or numbered for a customer.
8 represent Australia States & Territory, as there are 8

Any info on the 3 in the third picture?
^^^
The Stamp could be made by the same manufacturer at the time.
Doesn't mean they came from the same smelter.
I agree Chip but what smelter were thy from if not Perth mint?
do you know who made the GEOMIN ingots?
