Sugar Loaf rock in Rio de Janeiro (Brazil) is made of granitoid rocks (granite), which were formed by the collision of several plates which joined together and molded the western side of the former supercontinent of Gondwana (South America, Africa, Antarctica, Australia, and India).
Granitoid rocks are found all over Rio de Janeiro State (including Corcovado) and are estimated to be 560 million years old.
By the way, Sugar Loaf was recognized as one of the main geological monuments in the world during the 31st International Geological Congress, which took place in Rio de Janeiro in 2000.
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