Photograph of aerial view of Blue Diamond Plaster Company, showing location of specific buildings, ca.1930. At center the large area used by Blue Diamond Plaster Company has been highlighted, and text has been added to the image. The buildings have been drawn-in on the photographed terrain. The area lies between at the cross-section of 16th St. and Alameda St.; To the further right, Washington Blvd. has also been highlighted. Starting from the back left and moving right, the image identifies the "Sand Bunkers", "Mortar Plant", "Putty Plant", "Sand Storage", and "Sand Pit" on the far right. Near the center of the complex, the image identifies the "Crushed Stone Bunker", "Stucco Mill", "Machine Shop, "Train Loads of Rock", "Carpenter Shop", "Train Loads of Gypsum", "Stables", "Gypsum Storage", and "Plaster Mill". To the far right of the complex away from the buildings, the "Reserve Sand Property" and "B.D. Baseball Diamond" can be seen. Along the front of the complex, the "Warehouse" lies adjacent to 16th St., while the "Plaster Mill" and "General Offices" can be seen adjacent to Alameda street. In the extreme foreground and background, other industrial sites can be seen.