The Comstock Lode was the first major deposit of silver located in the United States, in 1858, in what is now Nevada but was then the western part of the Utah Territory.  It created a rush similar to the California Gold Rush, leading to the founding of Virginia City — a place of fabulous wealth and vice — and the creation of the state of Nevada.  The lode was pretty much played out by 1874.  Virginia City has only about 1,500 residents today and makes its money mostly off of tourism, because many remnants of its former splendor are still standing, out in what is now the middle of nowhere.