All I have is a story that I know is true, but I have lost the evidence to prove it! Silly me!
On the 3rd of January 1992, I visited the Royal Australian Mint in Canberra. Although I didn't know it at the time, it was the first day of use for the 1992 Barcelona Olympic commemorative dollar die in a 'mint your own' publicly operated coin press.
I put a two dollar coin in the slot and the coin press responded and struck a nice freshly minted Barcelona Olympic coin. I repeated the process three more times. That was only about ten minutes after the press started operation on the first day of life with the new commemorative reverse die. I was also presented with four small specially marked packets to put each coin in.
My mistake? I do not have the packets any more! With them, the market price for the coins would be double what they are now!
The 'mint your own' coins are listed at around $35, but my coins without the packets would not be worth much more than $20.
About 20,000 'mint your own' Barcelona coins were struck, WAY short of the full die life.
That's my story, and I am sticking to it!
At the 1992 Sydney Coin Show a few months later, I bought two proof silver Barcelona dollars with the continuous milling in the long box, new from the Mint for $30 each. I had no idea that they would zoom up in market value and they are valued at lots more than $30 each today.
I gave one of these to my sister, who has been actively collecting the Australian decimal series since it's introduction in 1966. I gave the other to my mother, both as Christmas presents.