Inorganic precipitation processes are capable of producing a wide range of morphological outputs. This range includes shapes with both crystallographic and non-crystallographic symmetry elements. Among the latter, morphologies that mimic primitive living organisms are easily obtained under different physico-chemical conditions including those that are geochemically plausible. The application of this information to the problem of deciphering primitive life on the early Earth and Mars is discussed. It is concluded that morphology cannot be used unambiguously as a tool for primitive life detection.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.