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 Marbles were originally made by hand.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
Lose Your Marbles board. In addition, a match of five will send marbles to the opposing player's board. The game in hard mode has a tactic after the player wins 6 games to change its skill and win every single other game. This cause the player to literally lose their marbles. Due to its simplistic controls, "Lose Your Marbles" can be played with two players with one keyboard. Lose Your Marbles also features a LAN multiplayer mode to connect 2 players over a local network. SEGA boldly claimed "More addictive than Tetris or your money back!" This was not a gimmick - SegaSoft