There are many advantages to choosing this plant-form calcium over a rock-source calcium. It is widely known that plants from nature are the preferred source of nutrients for the body. Of equal importance is that the plant-form calcium used in Vitamin Code RAW Calcium, Algas calcareas.sp, also provides 73 naturally occurring minerals and trace elements such as magnesium, silica, boron, vanadium and strontium that have all been linked to healthy bones.