Guaranteed Potency 11% Vegetal Silica form Springtime Horsetail and Oat Straw An Herbal Supplement World Organic Super Silica contains the highest potency of actual Silica of any leading brand, plus our extra complimentary ingredients Microcrystalline, Hydroxyapatite, and Boron as well as a special base of Silica rich, Oat Straw and trace minerals. Our special formulation combines the whole herb with all of the naturally occurring flavones found in springtime horsetail herb, as well an extra high potency extract to provide a balanced source of vegetal Silica. In the human body, silica is found in the hair, nails, and bones.