Marble (toy) Required" and "The Colbert Report". Currently, the world's largest manufacturer of playing marbles is Vacor de Mexico. The company makes 90 percent of the world’s marbles. Over 12 million are produced daily. Marbles are also made in China and may contain lead, arsenic, and/or cadmium due to the manufacturing process of old glass. Art marbles are high-quality collectible marbles arising out of the art glass movement. They are sometimes referred to as contemporary glass marbles to differentiate them from collectible antique marbles, and are spherical works of art glass. Collectible contemporary marbles are made mostly in the United States by
Elgin Marbles until the mid-20th century and have suffered irreparable damage by previous cleaning methods employed by British Museum staff. As early as 1838, scientist Michael Faraday was asked to provide a solution to the problem of the deteriorating surface of the marbles. The outcome is described in the following excerpt from the letter he sent to Henry Milman, a commissioner for the National Gallery. The marbles generally were very dirty ... from a deposit of dust and soot. ... I found the body of the marble beneath the surface white. ... The application of water, applied by a sponge or soft