SAPPHIRE-60/40 is 60% tin and the balance lead. A consistent and smooth flowing solder, 60/40 is the best selling alloy in the stained glass field. It melts at 372 deg F, and solidifies at 361 deg F. The “pasty range” (most solders melt at a higher temperature than they freeze at, the difference between these figures is the pasty range) of 60/40 is smaller than that of 50/50, giving the user a smoother bead. WARNING: This product can expose you to chemicals including lead, which is known to the State of California to cause cancer. For more information, go to www.P65Warnings.ca.gov.”