The cycle of rocks (Rock cycle) refers to the change of the three types of stone from one stone to another or may change back to the original type of the other stones.
Rock cycle (Rock cycle) means a change of the three rock types from one type to another type of stone or rock type may change back to the original again.
Rock cycle (Rock cycle) means the change of whole rock 3 type. From the Bloodstone is another type, or may change back to the original type of stone again.