Body piercing is frequently done in the form of a ladder. Modern body piercing practices also include dermal anchoring or dermal piercing, which combines piercing and implantation to create a single point of opening in the body (whereas pocketing creates two) to permit one end of the jewellery to show above the surface of the skin. While this technique can be performed almost anywhere on the body, as of 2007 it was popularly done between the eyes, on the chest, or on the finger, to simulate a ring. The practice of body piercing is subject to trends and fashions. Belly button and
Composition of the human body mass of the human body is made up of six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Only about 0.85% is composed of another five elements: potassium, sulfur, sodium, chlorine, and magnesium. All 11 are necessary for life. The remaining elements are trace elements, of which more than a dozen are thought on the basis of good evidence to be necessary for life. All of the mass of the trace elements put together (less than 10 grams for a human body) do not add up to the body mass of magnesium, the least common of the 11 non-trace elements.