Not entirely regular

If something tastes of sugar, you can say it tastes sugary. If something tastes of salt, you can say it tastes salty. So we see a pattern here, and try taking it further, for example, having boiled some rhubarb in a copper pan, one might find that it tastes coppery. Then we find that the hoped-for rule breaks down for iron. If you read enough of these posts, though, you might taste irony.