Dominoes spots from one to six are generally arranged as they are on six-sided dice, but because blank ends having no spots are used, seven faces are possible, allowing 28 unique pieces in a double-six set. However, this is a relatively small number especially when playing with more than four people, so many domino sets are "extended" by introducing ends with greater numbers of spots, which increases the number of unique combinations of ends and thus of pieces. Each progressively larger set increases the maximum number of pips on an end by three, so the common extended sets are double-nine, double-12,
Chinese dominoes to 14th centuries have survived. Unlike most modern tiles they are white with black and red pips. During the Qing dynasty (1644-1912), the suits known as "Chinese" and "barbarian" were renamed to "civil" and "military" respectively to avoid offending the ruling Manchus. Tiles with blank ends, like those found in Western "double-six" dominoes, once existed during the 17th century. These games employed two sets of "double-six" tiles. It is possible that these were the types of dominoes that made it to Europe the following century. Each tile pattern in the Chinese domino set is made up of the outcome of