Biominerals are biogenic hybrid ceramics evolutionary honed to high-performance materials with high functional density and damage tolerance. Their unique traits render them a source of inspiration for the novel design of materials and syntheses, motivating an in-depth analysis of their process-structure-properties relationships from a materials chemistry perspective. Biominerals are complex and hierarchically structured biomaterials composed of apparently simple inorganic minerals, such as calcium phosphate or calcium carbonate, interwoven with organic components. In the biosynthesis processes of these 'bioceramics', transient amorphous phases play a decisive role that subsequently crystallizes in a shape-preserving manner. Biominerals are often praised for their exquisite control over this process, reminiscent of the formation of glass-ceramics but occur at ambient conditions. While earlier studies highlighted near-to single-crystalline biominerals, complex polycrystalline features are more widespread yet challenging to account for. Here, we propose that (bio)ceramics whose crystal texture varies with depth are functionally graded materials that enhance the endurance against shard and blunt contact damage. We show that the formation of such complex crystallographic textures is inherent to their nonclassical formation via nanoparticle accretion processes and can be mimicked by biomimetic mineralization processes. This unforeseen process-structure-properties relationship highlights the still untapped potential of (bio)synthetic approaches that employ nanoparticle-based and nonclassical routes to generate functional materials.