Marble (toy) - Manufacture

Manufacture

Marbles are made using many techniques. They can be categorized into two general types: hand-made and machine-made.

Marbles were originally made by hand. Stone or ivory marbles can be fashioned by grinding. Clay, pottery, ceramic, or porcelain marbles can be made by rolling the material into a ball, and then letting dry, or firing, and then can be left natural, painted, or glazed. Clay marbles, also known as crock marbles or commies (common), are made of slightly porous clay, traditionally from local clay or leftover earthenware ('crockery'), rolled into balls, then glazed and fired at low heat, creating an opaque imperfect sphere that is frequently sold as the poor boy's 'old timey' marble. Glass marbles can be fashioned through the production of glass rods which are stacked together to form the desired pattern, cutting the rod into marble-sized pieces using marble scissors, and rounding the still-malleable glass.

One mechanical technique is dropping globules of molten glass into a groove made by two interlocking parallel screws. As the screws rotate, the marble travels along them, gradually being shaped into a sphere as it cools. Color is added to the main batch glass and/or to additional glass streams that are combined with the main stream in a variety of ways. For example, in the "cat's-eye" style, colored glass veins are injected into a transparent main stream. Applying more expensive colored glass to the surface of cheaper transparent or white glass is also a common technique.