Abstract: A glass material for mold pressing, comprised of a core portion and a covering portion. In one embodiment, the core portion comprises a multicomponent optical glass containing at least one readily reducible component selected from among W, Ti, Bi, and Nb and the covering portion comprises a multicomponent glass containing none or a lower quantity of the readily reducible component than is contained in the core portion. In another embodiment, the core portion comprises a fluorine-containing multicomponent optical glass, and the covering portion comprises a multicomponent glass containing none or a lower quantity of fluorine than is contained in the core portion. A method for manufacturing an optical glass element employing the above glass material that comprises heat softening a glass material that has been preformed into a prescribed shape, and conducting press molding with a pressing mold.

Abstract: A glass material for mold pressing, comprised of a core portion comprised of a multicomponent optical glass containing at least one readily reducible component selected from among W, Ti, Bi, and Nb, and a covering portion covering the surface of said core portion, comprised of a multicomponent glass containing none or a lower quantity of said readily reducible component than is contained in said core portion. A glass material for mold pressing comprising a core portion comprised of a fluorine-containing multicomponent optical glass and a covering portion covering the surface of said core portion, comprised of a multicomponent glass containing none or a lower quantity of fluorine than is contained in said core portion. A method for manufacturing an optical glass element comprising heat softening a glass material that has been preformed into a prescribed shape, and conducting press molding with a pressing mold, employing the above glass material of the invention.