The head on a ring is the component which holds and secures the stone. Heads can be bezels, Design by Alisa Unger which are the most secure, half bezel, six prong or four prong. Six prong are more secure than four prong because there is more metal covering and protecting the stone. If one prong breaks or wears away on a four prong head, the chances of the losing the stone are very good. A missing prong on a six prong head still keeps the stone in place, but should be replaced as soon as possible. Over time prongs on a ring will wear away, corrode, become brittle or break off. It is important to have your ring checked periodically by your jeweler to examine your head.