I’ve only used the Gold and Silver foils that came with my machine from Metallic Elephant. No issues. They seem to work great. I think you may be able to contact them through their web site for detailed compositional information. They have been very helpful.
@matthewodette28 So far my favourite has been API foils, these are available from Metallic Elephant.
Another well regarded foil company is https://www.foilco.co.uk/
I don't believe I have seen any modern companies selling pure gold or silver foils on an adhesive strip. But then again I haven't gone looking for it.
Mando in France sells true gold and silver foil.
https://mando.fr/index.php?dispatch=products.view&product_id=2100
I think the gold is 22k. But i would contact them first to know all the details for sure.
The main advantage of using real gold is bragging rights I guess...
I’ve only used the Gold and Silver foils that came with my machine from Metallic Elephant. No issues. They seem to work great. I think you may be able to contact them through their web site for detailed compositional information. They have been very helpful.