Physical Coins representing Blockchain (usable by the very poor)

This idea is to allow poor people to take part in crypto and stable-valued money without needing special technology.

My koin.tech k0in.com website is down, so I will publish here an idea for physical coinage system usable by very poor countries and people. These hard-to-counterfeit coins would represent money on a blockchain, and be usable by those not affording smart-technology. They could exchange the coins for its equivalent crypto, or vice versa.

The crypto would be frozen as soon as a physical coin was released, and unfrozen to they who returned the coin.

That way the physical money could be fluid with the wider-used cryptocurrency.