Home > Listing of Enamels > Lump/Frit/Square/20 MeshClick Image To View Larger 167 Chinese Red (lump) (op) Limited Availability $7.00 Quantity: - + Lump form enamel, Thompson Enamel for Copper,Silver, Gold, Iron and Steel. Should be fired at 1450 to 1550 degrees F.All Enamel is pre-1990, and lead bearing.