An edge surface of a magnetic-disk glass substrate containing an alkali metal component as a glass composition is a mirror surface, and in a bearing ratio curve of roughness cross-sectional areas obtained by measuring a surface roughness of the edge surface obtained by etching the edge surface by 2.5 m, a roughness percentage when a bearing ratio of a roughness cross-sectional area is 50% is 40% or more.

A method includes partially forming a top chamfer on a disc substrate with a first brush, and partially forming a bottom chamfer on the disc substrate with a second brush. The method also includes completing the formation of the bottom chamfer with the first brush, and completing the formation of the top chamfer with the second brush.

A method includes partially forming a top chamfer on a disc substrate with a first brush, and partially forming a bottom chamfer on the disc substrate with a second brush. The method also includes completing the formation of the bottom chamfer with the first brush, and completing the formation of the top chamfer with the second brush.

Methods of shaping a glass sheet each include a step of removing a first portion of the glass sheet to form a first beveled surface. The methods further include the step of removing a second portion of the glass sheet to form a second beveled surface. The methods still further include the step of removing a third portion of the glass sheet comprising a remainder of an end surface of an edge portion of the glass sheet. In further examples, glass sheets are also provided with a first bevel surface intersecting a first glass-sheet surface and an apex surface, and a second bevel surface intersecting a second glass-sheet surface and the apex surface. The glass sheet exhibits a probability of failure of less than 5% at an edge stress of 135 MPa.