The role of geometric decoration is central to any analysis of Islamic art; it is one of the unifying factors that, for thirteen centuries, have linked buildings and objects from all over the Islamic world across an enormous geographic span. (Grube et al, 161).
Islam transformed geometry into an art form. The usage of geometry throughout Islamic architecture opened windows of opportunity for applying the principles of repetition, symmetry, and change of scale. When these usages of geometry are practices they create a perplexing variety of effects. To achieve these effects diverse textures are applied to the building in attempt to unify the geometric principles. This concept is best expressed by the Bu- Inaniyya Madrasa in Fez, Morocco. The chiseled wood and decoratively placed tiles share the same decorative concept. .
Surfaces are another big part of geometry. The surfaces are either curved or flat and are most commonly embellished with brick or stucco. Patterns that are formed by this and eventually permit the play of light at a certain time of day and distance. The play of surfaces is excellently shown in Damghan, Iran at the Great Mosque. The Great Mosque shows this form of decoration by it's curved outline of the minaret. The design/ pattern is extruded beyond the base of the stucco and brick to show shade and in turn accent the pattern.
The star is another fundamental part of Islamic geometrical design. It can be found with six, eight, sixteen, or more points. As the most used shaped in all of Islamic architecture can be used in two-dimensional or three-dimensional ways. Usually the three dimensional stars are used in domes to link surfaces of to decorate fittings inside buildings. For example, the ceiling of the Tomb of Hafiz at Shiraz contains a sixteen-point star that is connecting many different shapes spread throughout the ceiling. All of the elements of decorative geometry in Islamic architecture represent the uniqueness and specialty of the design.