billes

Billes is a plural noun used in French to denote small spherical objects, most commonly marbles. In English-language contexts, billes is rarely used outside technical or francophone references, where it refers to either marbles or rolling spheres used in bearings.

As marbles, billes are typically glass but can also be made from agate, stone, or clay. They range in size from a few millimeters to several centimeters and are used for play, collection, or decoration. Common varieties include transparent or translucently colored glass marbles, opaque solid colors, and patterned types such as cat’s eyes and millefiori designs. The production of glass marbles involves molding or pressing glass and then finishing to achieve a smooth, round surface.

As bearing balls, billes are precision-grade spheres used as rolling elements within ball bearings. They are manufactured from steel (notably bearing steels such as AISI 52100), stainless steel, or ceramic materials. Sizes span a broad spectrum from under a millimeter to several millimeters, depending on the bearing design. Bearing balls are engineered for tight tolerances, roundness, and surface finish to minimize friction and wear, supporting radial and axial loads in machinery, automotive components, aerospace systems, and electrical equipment. They are typically housed in cages and sealed to protect against contamination.

In manufacturing and trade, billes (as marbles or as bearing balls) are produced, tested, and specified according to standards that address material, diameter, roundness, and surface finish. The term emphasizes the spherical shape and its functional or decorative use. See also marble and ball bearing.