To obtain a coating material which forms a light shielding film excellent in strength, light transmittance, etc., when applied to the surface of a lamp and fired by incorporating polycrystalline silica, manganese doped iron oxide and a silica-base powdery glass.

The coating material contains polycrystalline silica, manganese doped iron oxide preferably represented by the formula (Fe1-xMnx)2O3, (where 0.05<x<0.4) and a silica-base powdery glass preferably having a compsn. consisting of two or more selected from silica, boron oxide and alumina and 600-1,400°C softening point. The solid constituents contained in the coating material preferably include 5-20 wt.% silica-base powdery glass and the solid constituents except the powdery glass are preferably 20-80 wt.% polycrystalline silica and 80-20 wt.% manganese doped iron oxide. The objective light shielding film formed on a lamp using the coating material does not cause peeling, cracking, discoloration, etc., even by exposure to ≥700°C for ≥200 hr during lighting.