melting down

鋳つぶし／ melting-down　—　Making

Melting a coin back into a lump of metal.

Overview: the world — What Became Money / War Seizes Materials — Overview: the world　What Became Money ／ War Seizes Materials

If the intrinsic value becomes higher than the face value, it is more profitable to melt the coin down. In this way, good coinage disappears from the market. ⚠ Melted coins do not survive as historical records. This is why the quantity in circulation cannot be estimated from the "number of surviving specimens".