Steelies
Steelie is slang for a ball bearing used as a marble. These can be made of any metal, but are typically made of steel. Steelies have been outlawed for tournament play in the United States, explains the American Toy Marbles website.
Aggies
Aggies are shooters made of any type of agate. Agates are a hard, fibrous type of quartz which come in a variety of colors and patterns. They are highly prized for their uniqueness and beauty.
Cat&'s Eyes
Cat&'s eyes were originally made in Japan in the 1950&'s. They are clear glass marbles with swirls of colored glass injected into their centers. Today, they are not as popular because they are mass produced and their colors are more uniform and less unique.