Beautifully engraved Certificate from the Grand Coulee Mines issued in 1937. This historic document was has an ornate border around it with a vignette of and eagle. This item is hand signed by the company's president and is over 63 years old. These mines are located in the Grand Coulee Dam area. The Grand Coulee Dam sits deep in the Columbia River Gorge of central Washington. It is located about 90 miles west of Spokane, 105 miles South of Canada's boarder, and about 250 miles east of Seattle. The Grand Coulee Dam was built from 1933 to 1975, it is 550 feet tall, from the 500 foot wide polished granite base, to the 30 foot wide crest which supports a paved two lane road. When you include the third power house, Grand Coulee Dam is almost 1 mile long. There is enough concrete in the Grand Coulee Dam to build a 60 foot wide highway four inches thick, from Los Angeles to New York City. The base of the Grand Coulee Dam is almost four times as large as the Great Pyramid built by the Pharaoh Khufu (Cheops). It stands 550 feet in height, from the bedrock to the blacktop! Like the Pyramid, the Grand Coulee Dam has its galleries. They serve for gate inspections and control, drainage, regrouting, cooling, and other purposes. There are over eight and a half miles of corridors throughout the inside of the Grand Coulee Dam. In size, it is the second structure created by man to exceed that of the Great Pyramid [c. 2680 B.C.E.] The first structure built after Khufu's pyramid would be the Great Wall of China [c. 215 B.C.E.], which is 1400 miles long and varies between 18 and 30 feet in height.