Home > Listing of Enamels > Vintage Enamel > Thompson TransparentsClick Image To View Larger 425 Flux (tr) *Supplies are extremely limited!* $8.00 Weight 1 oz ($8.00) 8 oz ($64.00) 16 oz ($128.00) 1877:=:8,1879:=:64,1880:=:128 Quantity: - + Transparent, cataloged, Thompson Enamel for Copper, Silver, Gold, Iron and Steel. This enamel is "medium fusing" and should be fired at 1450 to 1550 degrees F. for approximately 2 to 4 minutes. All Enamel is pre-1990, 80 mesh and lead bearing.