It is well known by far that biological organisms could arrange themselves in sophisticated and complex structures, which compete or overcome the top technology products available and which exhibit peculiar optical behavior. In recent years, the porous silica structures (frustules) created by living diatoms are under study for several nano-engineering applications based on bio-mimetic approaches. The diatoms are microscopic algae enclosed between two valves of hydrated amorphous silica. They spontaneously arise in every aquatic environment. More of 104 types of diatoms have been discovered and classified by different shapes of their cell walls. These intricate structures, called frustules, show symmetric patterns of micrometric and nanometric pores. Due their peculiar structures and large variety of morphologies, a widespread interest about diatoms and their possible use in nanosciences and …