Final answer:
Limestone and basalt were used to finish the exterior of the pyramids in Egypt.
Step-by-step explanation:
The stones used to finish the exterior of the pyramids in Egypt were mainly limestone and basalt. Limestone was a commonly quarried stone all along the Nile Valley, and it was used for the smooth sides of the pyramids. Basalt was also used, particularly from the wadis (valleys) of the eastern desert, to provide a more durable and hard material for certain parts of the pyramids.