The 1906 San Francisco earthquake flattened the new steam crushing plant and temporarily halted operations . Rail operations were disrupted , and the quarry operation was devastated . The earthquake 's destruction created a demand for construction . In the following years , Granite Rock Company supplied materials for a number of buildings in San Francisco and around the Monterey Bay area . Among those still standing are the old Gilroy City Hall and the old San Francisco Wells Fargo Building . At the quarry in Aromas , California , expansion was taking place . Demand for materials allowed purchase of a Marion Steam Shovel in 1909 for loading quarry cars . A second Marion shovel was purchased in 1911 with a larger rock crusher capable of producing 175 tons per hour . The older crushers were converted to electric power and five narrow-gauge railway steam locomotives were purchased to move broken rock from the quarry face to the steam crusher over of quarry tracks
1906 San Francisco earthquake
1906 San Francisco earthquake
Graniterock