How Are Glass Marbles Made?
The glass marbles with which you play games are made by forming molten glass into balls. Bright swirls and stripes are added by twisting colored strips of red-hot glass together. The hot glass is cut into small cubes and dropped into a shaping machine. The moving rollers of this machine shape the glass into round marbles.
Mass-produced marbles use multiple nozzles to combine streams of liquid glass that are cut into even-sized lumps and passed between two parallel, rotating screw threads. As the screws rotate, the marbles are moved along the production line, constantly rolling to form into perfect spheres as they cool. Fancier marbles are sometimes coated with powdered glass of other colors as they roll.
People have been playing with marbles for hundreds of years. The first marbles were round pebbles. In the 1700s, people began making small balls from marble stone, which is where the marble got its name. The oldest marbles were handmade by rolling clay, carving ivory or grinding stone. Glass marbles can also be made by hand in a process that resembles making seaside rock. Molten colored glass is rolled into rods and stacked together to form a pattern.