Pewterers
They add one lb. of glass tin to one quintal of fine tin, which makes the tin ticker. There is two kinds of tin, one which flows better, like lead, while the other one is sour and can be made thicker. They are casted in thick and solid tin molds or, to cast more neatly, in chisel—engraved copper molds, or stone or earth [molds]. Latten scrapings mixed in make the tin more breakable and harder, and more difficult to work with. They cast in the very hot molds some very hot tin. They perfume their tin molds with resin candles.
Sour tin is often mingled with salmons, easy to cut but difficult to work with and melts if it is not mingled with the other soft one. And thus it would become leftover.