Apatite is often a hexagonal crystal, most commonly found in shades of green, varying from light green to dark green. It may also be found in blue, brown, purple, brown, orange, and clear. It is made up of phosphorus, a component of fertilizer, and this is the main reason it is mined today. Nice inclusion-free well-shaped colorful crystals are more difficult to find, and these are often used in jewellery instead of the production of phosphorus.