Provided herein is a process for randomly patterning a plurality of carpet tiles, each tile having a composite pattern containing at least a base pattern and an overlay pattern. When installed, the random order of patterning results in random tile placement and an overall random appearance. The overlay patterns are randomly chosen from a library of patterns until each individual pattern has been used to create a tile series. The overlay patterns may be manipulated by rotating, mirror-imaging, rotating and mirror-imaging, or repositioning to produce additional variations and increase the number of tiles in the series. The base pattern may optionally be manipulated before being incorporated into the composite pattern. A tile collection, containing such randomly ordered composite patterns, is also described.