Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Ruggles Mine is an open-pit mine that is no longer in operation and has been turned into a tourist attraction. The mine is located 30 miles (48 km) northwest of Concord, in Grafton, New Hampshire, a short distance from Route 4 at the village green. The spacious pit includes tunnels and underground chambers, some of which are filled with water, for exploring. Visitors are allowed to keep any of the various minerals that are to be found on the mine floor or that can be hammered loose from the walls of the pit. The mineral deposits found in New Hampshire, known as the Littleton Formation, are from the Devonian period and dated by geologists to be roughly 350 million to 400 million years old. Over 150 minerals have been discovered at the mine, mica being the most prevalent, but also including feldspar, beryl, amethyst, rose/smoky quartz, and garnet. Depositsof the rare uranium minerals, such as uranophane, torbernite, and autunite, have been found.