Tank for melting solder glass

A melting tank for melting solder glass powders typically comprised of PbO and B2O3 and other minor ingredients. The tank contains surfaces exposed to the atmosphere and surfaces in contact with the molten solder glass. The surfaces of the tank that are in contact with the melt are comprised substantially entirely of iridium. Preferably, the surfaces exposed to the atmosphere contain a coating thereon of a metal or metal oxide such as palladium, ruthenium, rhodium, aluminum oxide, calcium oxide, cerium dioxide, dichromium oxide, hafnium dioxide, magnesium oxide, silicon dioxide, thorium dioxide, zirconia, mullite, magnesia spinel or zircon. It is also preferred that the cavity of the tank have a generally circular shape. The melting tank may be readily fabricated by wrought metallurgical processes or by electroforming.