Marble (toy) conventions. Additionally, many glass artisans produce art marbles for the collectors' market only, with some selling for thousands of dollars. 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 Marbles were originally made by hand.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
Marble (toy) the line and trying to win as many marbles as possible.If some marbles are left in the line after each player takes a chance, the players again throw their marbles perpendicularly to this line and start to roll their marble to hit the line according to the above rules. This process is repeated until all marbles are taken in the game. In Uganda, a popular marbles game is called "dool". It requires a small pit dug in the ground for two or more players, each with his own marble. To improvise, Ugandans also use the seeds of a candlenut tree,