The present invention is focused on a revolutionary, low-cost (highly-scaleable) approach for the mass production of three-dimensional microcomponents: the biological reproduction of naturally-derived, biocatalytically-derived, and/or genetically-tailored three-dimensional microtemplates (e.g., frustules of diatoms, microskeletons of radiolarians, shells of mollusks) with desired dimensional features, followed by reactive conversion of such microtemplates into microcomponents with desired compositions that differ from the starting microtemplate and with dimensional features that are similar to those of the starting microtemplate. Because the shapes of such microcomponents may be tailored through genetic engineering of the shapes of the microtemplates, such microcomposites are considered to be Genetically-Engineered Materials (GEMs).