I was fortunate to meet a retired Perth Mint quality control manager at a Christmas lunch, and got a lot of insights into QC operations at the mint.
This person was not a stacker (clearly already has immense wealth from other endeavours), but had decades of passionate involvement in R&D and in-line QC at the mint. Any more info would probably dox them.
Apparently there was a major management restructure around 5years ago and a lot of top experienced workers were let go in a kind of ‘corporatisation’ strategy.
We’re talking approx 150 years of manufacturing and QC experience.
it was amazing hearing about how the special designs and LE coins were created, and how few people were selected to inspect quality of the higher value counts.
It also accounts for why larger sizes (1/2kg, 10oz etc) were dropped from production.
I think the older coins (especially ones larger than 1oz) in good condition will remain excellent investment value and represent the height of world class manufacturing.
there was not a lot of positive comment on the new management team, but have to keep in mind this is feedback with a bias.