The paper says that the name "Mercury" refers to the importance of the mercury industry during the California Gold Rush, when the city's New Almaden Mines (now Almaden Quicksilver County Park) were the largest producer of mercury in North America. The name has a dual meaning, as Mercury is the Roman messenger of the gods as well as the god of commerce and thieves, known for his swiftness, and the name Mercury is commonly used for newspapers without the quicksilver association.