The granite of the pão de açúcar mountain, which belongs to the Rio de Janeiro suite of mountains,  has only recently had its magmatic structure investigated and unraveled. 

The suite of mountain formations contains many different foliated granitoids plutons, displaying chiefly crustal Stype affinities -  Pão de Açúcar Granite, Corcovado Granite and Cosme Velho Granite.

Recent geocrhonological studies, using a SHRIMP (Sensitive High Resolution Ion Microprobe) systematic found there to be a crystallization age of ca 560 Ma - This age acts as an international geological reference for the final amalgamation of the Gondwanaland Supercontinent, during the Brasiliano / Pan-African Orogenic Cycle termination.