Most of the diamond discoveries have been in glacial deposits in southeastern Wisconsin, mainly in the late s when water wells were dug in the glacial drift. The map below shows the locations of diamond "finds" in the Great Lakes region, and the possible paths that they took to get to those locations. The origins of diamonds in the region can be traced back to the Precambrian rocks of the Canadian Shield , the southern boundary of which is also shown on the map below.
Source: Unknown The first documented diamond discovery in Wisconsin was made during the digging of a well in by Charles Wood, in southwestern Waukesha County. The digging had passed through 10 to 15 m of clay, and then through loose gravel, when a two meter layer of hard yellow material was struck. While penetrating this stratum, a hard stone of unknown identity was struck.
The jeweler refused, and Mrs. Wood sued. The Supreme Court ruled that the stone was the property of the jeweler because he believed it was topaz when he bought it. The crystal, originally known as the Waukesha Diamond and later, the Eagle Diamond, is a warm yellow color and weighs The stone was on public display at the museum until the evening of October 29, , when "Murph the Surf" broke in, and departed with the Eagle Diamond and other gems.
Haggerty, who's also the chief exploration officer of Youssef Diamond Mining Company which owns mining concessions in Liberia , told Science magazine that while the plant is a good indicator of a kimberlite pipe, it's good to follow a rule of sixes to determine which pipes will hold diamonds. So finding a Pandanus candelabrum isn't a sure sign you'll strike it rich, but still, having a plant do the initial scouting work for prospectors could be a huge time and money saver.
With its spiky leaves, above-ground stilt-like roots similar to mangrove trees, and tendency to grow to heights of about 32 feet 10 meters , the plant's easy to spot -- even from the air.
While scientists have previously used termite mounds to pinpoint deposits of kimberlite in the soil, this is the first time a plant that does the same thing has been identified, according to the abstract accompanying the research. About the discovery, Steven Shirey , a geologist specializing in diamond research at the Carnegie Institution for Science in Washington, D.
Be respectful, keep it civil and stay on topic. We delete comments that violate our policy , which we encourage you to read. Discussion threads can be closed at any time at our discretion. Diamond prospectors know that the secret to finding diamonds is to locate rocks called kimberlites. A new study in Nature this week may help them focus their search a bit more closely, and also reveals a new understanding of the Earth's mantle.
Kimberlites — named after the South African town of Kimberley where they were first diamond was discovered — are generally only found in very old parts of the Earth's crust. They are the sites of small but violent volcanic eruptions that brought material — including diamonds — spewing to the surface. No one has ever seen a kimberlite erupt — the most recent took place about 40 million years ago, said study author Kevin Burke, a geologist at the University of Houston.
Scientists have known that kimberlites beneath Earth's surface erupt when shifting tectonic plates push them over plumes of heat rising from deep within the mantle. But these plumes are confined to certain regions of the mantle. Burke's work reveals the best places to look for diamond-bearing kimberlites are the boundaries between the parts of the mantle that enclose plumes and those that don't.
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