Home > Listing of Enamels > Vintage EnamelClick Image To View Larger 757 Flux for Silver (clear transparent) $0.00 WEIGHT 1 oz. (+$6.00) 4455:+:6 Quantity: - + Medium fusing Thompson Enamel for Silver. Should be fired at 1450 to 1550 degrees F. All Enamel is pre-1990, and lead bearing.