10cp = 1sp
10sp = 1gp
5gp = 1ep rarely used
10gp = 1pp
10pp = 1mp (mythril)
10mp = 1op (orichalcum)
10op = 1ap (adamantium adamantite)

The top three can only be exchanged at specialized metals dealers but there is no fee to the public. These dealers exist everywhere adventurers go they get reimbursed through the township for the service.

Regular shops will accept any denomination but can't give change if you exceed their total store of coins.

1ap would then be worth 10,000gp so 100 of those would be a million gold. Alice is basically a walking safe if you want. If someone knew they would loot her body though, so be discrete.