I'm not familiar with this, but according to his links it seems there's a fixed ...

vladvasiliu on Aug 11, 2020 | parent | context | favorite | on: Mon Valley communities test “time credits”, a new ...

I'm not familiar with this, but according to his links it seems there's a fixed exchange rate of 1 € = 1 G. I think it's not exactly a "different currency" it's more like chips in a casino.