Lonrho Mining made news this week when it revealed a 131.5-carat white rough diamond recovered from a bulk sample at its Lulo concession in Angola. The impressive gem-quality diamond, which is the width of a softball, is the largest find since the company started prospecting in Lulo in 2008.
The company has yet to estimate how the gemstone would be cut, but managing director Miles Kennedy called the stone's size "incredible" and noted that there is strong indication that the kimberlite pipe that produced the mammoth stone is very close by.
This is significant because kimberlite pipes are the source of most of the world's commercial diamond production. Geologically, these pipes of volcanic rock act as vertical superhighways from deep within the earth to the surface. Among the elements being pushed to the surface are precious gemstones, including diamonds, amethyst, banded agate, jasper, peridot, garnet, quartz, calcite, barite, lamproite and hematite.
Get in on the fun here at home...
Did you know that a kimberlite pipe and its treasure is accessible to the public at Crater of Diamonds State Park in Arkansas. For a $7 fee ($4 for children), amateur diamond hunters can seek their fortunes as they scour a 37 1/2-acre plowed field, which is actually the eroded surface of an ancient volcanic crater. It's the only place in the world where the public can search for diamonds and keep what they find.
More than 500 diamonds were found at the park in 2011, according to Park Superintendent Justin Dorsey. "We registered 30 diamonds over one carat," he told The Philadelphia Inquirer. The 8.66-carat "Illusion Diamond" (third) and the 6.67-carat "Teamwork Diamond" (ninth) rate among the 10 top diamond finds at the park in the past 40 years.
In the early years of the mine, between 1907 and 1932, the equipment used to sift soil were screens with mesh larger than 1/16 inch. Due to this large dimension, thousands of smaller diamonds were allowed to pass through. In recent decades, the small diamonds have become a mother lode for recreational diamond diggers.
Dorsey said that he expected the 30,000th diamond to be found at the park this year. The three most common diamond colors found at the Crater of Diamonds State Park near Murfreesboro are white, brown and yellow.
Park staff is available to assist in identifying the various gemstones, including diamonds. Every diamond discovered is certified and listed on the Crater of Diamonds State Park official website. See this link for the latest finds...