Lost mines are a popular form of lost treasure legend. The mine involved is usually of a high-value commodity such as gold, silver or diamonds. Often there is a map (sometimes called a "waybill") purportedly showing the location of the mine. Common reasons given for the mines being lost include:
The mine is discovered and worked by a recluse who refuses to divulge the location, and dies without revealing the location.
The mine is worked by native peoples who refuse to divulge the location to others.
The mineral deposit is discovered in a remote location, and upon returning to the area the discoverer cannot find it again.
The discoverer dies of hunger, thirst, or exposure shortly after discovering the deposit, and his body is found with rich ore specimens in his possession.
The discoverers are killed by hostile natives. Sometimes the natives cover up the entrance to the mine.
In Spanish colonies in the New World, many lost mines were supposedly worked under the direction of Jesuit priests before their sudden expulsion in 1767.
Some lost mine legends have a historical basis; some have none. But the lure of lost mine legends is attested by the many books on the subject, and the popularity of publications such as Lost Treasure magazine.
^I. A. Mumme (1982) The Emerald, Port Hacking, New South Wales: Mumme Publications, pp. 21–22.
Dobie, J. Frank (1930). Coronado's Children. Southwest Press – Texas folklorist J. Frank Dobie collected many tales of lost mines of the American Southwest in the collection Coronado's Children. The title refers to those who followed the legends of hidden riches, like Coronado did in the 17th century.
Jameson, W.C. (1993). Buried Treasures of the Rocky Mountain West. August House