Lake Ellen Kimberlite the material, though few are of gem quality and size. While there was considerable interest in diamond exploration in Michigan’s Upper Peninsula and northern Wisconsin for several years, no diamonds of commercial interest have been found. Lake Ellen Kimberlite The Lake Ellen Kimberlite is a poorly exposed volcanic breccia located about northeast of Crystal Falls in the Upper Peninsula of Michigan. The first publication in 1981 describing the feature led to speculation that this or similar kimberlites in the area might have been the source of the diamonds discovered a century before in Wisconsin as well as a period of
Gemstone File Gemstone File The Gemstone File is a conspiracy theory document attributed to Bruce Porter Roberts. In 1975, "A Skeleton Key to the Gemstone File" appeared and is generally attributed to Stephanie Caruana. The "Key" is purportedly a synopsis of Roberts' documents that presents a chronicle of interlocking conspiracies, including claims that world events since the 1950s were shaped by suppressed information, the names of supposed shooters of President John F. Kennedy, and suggested connections between a number of political assassinations which occurred within a relatively short time frame. Authors James McConnachie and Robin Tudge called it "the original mega-conspiracy theory."