Ecclesiastical ring gold, stone-set ring. Roman Catholic bishops traditionally have their episcopal ring set with an amethyst. Aside from the rings a bishop purchases or is given by others, his rings belong to the Church; he will have inherited the previous bishop's ring collection, which is held in trust. While all hierarchs are accorded the honor of being buried wearing a ring, all rings belonging to the Church will be returned to the Church upon the retirement or death of any hierarch. In a Decree of Pope Boniface IV (A.D. 610) it describes monks raised to the episcopal dignity as "anulo pontificali
X-ring chain is in contact with the chain plates) when under pressure. Therefore the friction in X-ring chain does not increase much when pressure is applied by the chain plates. X-ring chain The X-ring chain is a specialized type of sealed roller chain used to transfer mechanical power. Like the O-ring chain it is used in high performance motorcycles. It uses X-ring seal to keep lubricant(usually grease) in place. It has higher performance (in terms of durability, lifetime, and power loss) than non-O-ring chain as it has less friction than O-ring chain which also increases reliability. It can last twice as long