Here is a little preview of my current project, "cryptodeck"
This card is made of .999 fine silver, weighs just over 1oz and are sourced and etched in the UK. This one serves as a prototype for my full deck which will be released in 4 waves of 13 cards, starting with spades.
There are no absolute rules to any trades or sales in respect of the crypto used to pay. Naturally the courtesy in Collectables is that the item IS actually collectable and valuable. And, as also seen, those items don't have to be BTC branded or flavoured items
These were me expanding on the ideas and playing with new ones at the same time. The Karpeles note is currently unique with there being a 2nd grade copy of the Andreas note, which I plan to keep for personal reference The onboard NFC tag is of course fully programmable with something like NFC Tools available on App stores.