I ran across a cold storage company that is printing bitcoin addresses and QR codes on metal cards. I'm interested in how they're doing this and whether SSL.com would be of any help. The only clue I have is this explanation from their website:
"Utilizing offline AES-256 encryption*, your newly generated or existing Private Key can never be known to us or any other entity that does not know your personally chosen passphrase.
The encryption process is performed in your own browser – not on our servers – so your passphrase is never seen by us. You can even disconnect your device from the Internet while generating and encrypting a new encrypted Private Key (or encrypting an existing one) and re-connect to complete your order. This can help to ensure that your Private Key and chosen passphrase are not potentially compromised."
How would I do the same?