Limpet teeth surpass spider silk as strongest natural material, says study

Telegraph : The tiny teeth that cover the tongues of limpets, a type of aquatic snail with a conical shell, are made of microfibers of goethite, an iron-based mineral. Used to scrape algae from rock surfaces, the teeth are superstrong and resilient. To test just how strong, researchers used focused ion beam microscopy to isolate a sample of the material and atomic force microscopy to test its tensile strength. According to their paper , published in the Royal Society journal Interface, they found that the material’s strength ranged from 3.0 gigapascals to 6.5 gigapascals—much stronger even than spider silk—and was independent of the sample’s size. The researchers say the material’s extreme thinness precludes the presence of holes or other flaws that could weaken the structure. The fibers are also tightly packed together. Such a strong, fibrous structure could have many uses, such as in cars, boats, and aircraft.