In KQC, the coins in the sockets were 'gold coins'. In KQ6 Hintbook known as the 'dead man's Coins', or the 'Deadman's Coins'. In KQ6 they are often described as the 'old coins'. The C marking is not explained. It could refer to the Crown, or perhaps "coin", or 'cent', or perhaps it could represent 'Charon', a clue to its use.