Have beautiful hair, skin and nails! Prairie Naturals ultra-silica is a natural source of silica that nourishes hair, skin and nails while supporting the skeletal system. Ultra-silica provides a superior source of organic silica from the aqueous extract of Spring Horsetail (Equisetum arvense). specially processed to provide a readily assimilated and abundant source of trace minerals, ultra-silica strengthens and beautifies hair, skin, nails and, most importantly, bones!.