A colorless soda-lime glass composition comprising by weight from 68 to 78% SiO.sub.2, from 8 to 18% Na.sub.2O, from 0 to 10% K.sub.2O, from 7 to 12% CaO, from 0 to 10% MgO, from 0 to 10% ZnO, from 0 to 10% BaO, from 0 to 3% Al.sub.2O.sub.3, from 0 to 1% B.sub.2O.sub.3, from 0 to 1% SrO, less than 0.078% total sulfur expressed in the form of SO.sub.3, at most 0.12% total cerium expressed in the form of CeO.sub.2, from 50 to 1200 ppm total iron expressed in the form of Fe.sub.2O.sub.3, without the intentional addition of Mo, As, Sn and Sb species, and with a redox lower than 45.

This disclosure relates to glasses and glass articles. The glass articles include flat glass suitable for use in display devices, such as electronic devices, including smartphones, smart watches and tablet computers. A method of making glass articles is described as well.

Proportions of the element erbium, the element aluminum, and the element phosphorus are adjusted during optical fiber preparation so that aluminum phosphate is formed around the element erbium in a prepared optical fiber, a probability that the element erbium in the optical fiber transits to a high energy level is reduced, and an excited-state absorption effect of the element erbium in the optical fiber on an optical signal is suppressed.

An optical glass includes, in terms of mol % of cations, a total amount of La.sup.3+, Y.sup.3+, and Gd.sup.3+ components falling within a range of from 5% to 65% and a total amount of Zr.sup.4+, Hf.sup.4+, and Ta.sup.5+ components falling within a range of from 5% to 65%, and a relationship expressed in Expression (1) given below is satisfied. (La.sup.3++Y.sup.3++Gd.sup.3+)(Zr.sup.4++Hf.sup.4++Ta.sup.5+)400(%).sup.2.