Constructed in 1854, Casa Grande was the residence of the manager of the New Almaden Mining Company until 1925. It has subsequently been used as a club, restaurant, bar, brothel, etc. Time and inadequate maintenance took a heavy toll on the building until it became part of the Almaden Quicksilver County Park. Under the guidance of Architectural Resource Group, it has been restored to its prime state, using Saint Astier® Natural Hydraulic Limes, when the structure was covered with a lime plaster, scored to simulate ashlar masonry.