Russian pyramid, also known as Russian billiards (, ), is a form of billiards played on a large billiard table with narrow pockets. It is popular across Eastern Europe as well as countries of the former Soviet Union/Eastern Bloc. In Western countries, the game is known as pyramid billiards, or simply pyramid within professional circles. Equipment Table: Playing-surface sizes vary. The official tournament size is , the same size used for professional snooker. Smaller sizes as used by other cue sports are also found in less-formal venues. The used in Russian pyramid tables are typically much thinner than those of pool and snooker tables, but is occasionally heated, similar to carom billiards tables. Balls: There are sixteen balls, fifteen and a , but in contrast to pool, the numbered balls are usually white, and the cue ball is red or yellow. They are typically larger and heavier than other types of billiard balls. The official tournament size is in diameter, weighing approximately 255g, while smaller balls – e.g., , , and (regular pool ball size) – are available for smaller table sizes. The old tournament size was 68 mm in diameter. Pockets: The are only 3 mm (approx. in) wider than the diameter of the ball, while the are 12–13 mm (approx. – in) wider than the diameter of the ball. This requires great precision to pocket a ball in such tight pockets. Cues: Due to larger ball size, the cues used for Russian pyramid are slightly thicker and heavier than those of pool cues, and the tip diameter is wider (up to 15 mm), in comparison to 10–13 mm used in pool cues. Specialty shots like and are usually more difficult to perform with a Russian pyramid cue, due to its heavier nature. These shots are also not allowed in official tournaments, doing so may result in a . Rule variations There are several rule variations of Russian pyramid. All games begin with fifteen numbered white balls in a , as in straight pool, eight-ball and blackball. Players may pocket any object balls on the table regardless of number, and the first player to pocket eight or more balls wins the . In addition, shots do not have to be . Depending on the game variant some specific balls may have to be in specific positions within the rack. The first player firmly s the rack with the from