Silica 500 from World Organic in a natural herbal supplement made with 10% vegetal silica from springtime horsetail. This product delivers the highest potency of actual Silica of any leading brand. Our special formulation combines the whole herb with all of the naturally occurring flavones found in springtime horsetail herb, as well as extra high potency extract to provide a balanced source of vegetal silica. Silica helps support healthy hair, nails and bones.