Uncle Sam (diamond)
Encyclopedia
Uncle Sam is the nickname for the largest diamond
ever discovered in the United States. It was found in 1924 in Murfreesboro, Arkansas
at the Prairie Creek pipe mine, which later became known as the Crater of Diamonds State Park. The diamond was named "Uncle Sam" after the nickname of its finder, Wesley Oley Basham, a worker at the Arkansas Diamond Corporation.
The rough diamond as originally discovered weighed 40.23 carats (8.046 g). It was faceted twice by Schenck & Van Haelen of New York, a company which specialized in Arkansas diamonds and had handled over 14,000 of them. The company described those diamonds as being so hard that they could only be cut using powder of other Arkansas diamonds. The final result was a 12.42-carat (2.484 g) emerald-cut
gem. It was characterized as M on the diamond color
scale; this nominally corresponds to a faint yellow color, but the visual impression of Uncle Sam has been variously described as white or slight pink. Judging from the color, the diamond is most likely of pure IIa diamond type
meaning the amount of impurities is below a few parts per million. The clarity
of the stone was assessed as VVS1, which stands for Very Very Slightly Included and means the stone has minute non-diamond inclusions that are difficult for a skilled grader to see under 10x magnification.
The diamond was owned by the Peikin Jewelers of Fifth Avenue, New York
. It was lent by Peikin to the American Museum of Natural History
for temporary display and storage. In 1971 it was acquired by a Boston dealer, Sidney de Young, and sold for $150,000 to an anonymous private collector.
The discovery of Uncle Sam arguably rescued the Arkansas Diamond Corporation, which had a debt over US$276,470 by that time and was going to be shut down in the winter of 1924. The number of diamonds found on the surface was decreasing, and the cost of digging operations was estimated as higher than the expected diamond recovery. Not that the value of the diamond was sufficient to cover the debts, but the discovery lifted the spirits enough to keep the surface operations. Currently, the Crater of Diamonds State Park in Arkansas is the only public diamond mine in the world. Over 75,000 diamonds have been found here since the opening of the park in 1906. The place where Uncle Sam was discovered is marked, and many additional diamonds have been found there.
Diamond
In mineralogy, diamond is an allotrope of carbon, where the carbon atoms are arranged in a variation of the face-centered cubic crystal structure called a diamond lattice. Diamond is less stable than graphite, but the conversion rate from diamond to graphite is negligible at ambient conditions...
ever discovered in the United States. It was found in 1924 in Murfreesboro, Arkansas
Murfreesboro, Arkansas
Murfreesboro is a city in Pike County, Arkansas, United States. The population was 1,764 at the 2000 census. The city is the county seat of Pike County....
at the Prairie Creek pipe mine, which later became known as the Crater of Diamonds State Park. The diamond was named "Uncle Sam" after the nickname of its finder, Wesley Oley Basham, a worker at the Arkansas Diamond Corporation.
The rough diamond as originally discovered weighed 40.23 carats (8.046 g). It was faceted twice by Schenck & Van Haelen of New York, a company which specialized in Arkansas diamonds and had handled over 14,000 of them. The company described those diamonds as being so hard that they could only be cut using powder of other Arkansas diamonds. The final result was a 12.42-carat (2.484 g) emerald-cut
Diamond cut
A diamond cut is a style or design guide used when shaping a diamond for polishing such as the brilliant cut. Cut does not refer to shape , but the symmetry, proportioning and polish of a diamond...
gem. It was characterized as M on the diamond color
Diamond color
A chemically pure and structurally perfect diamond is perfectly transparent with no hue, or color. However, in reality almost no gem-sized natural diamonds are absolutely perfect. The color of a diamond may be affected by chemical impurities and/or structural defects in the crystal lattice...
scale; this nominally corresponds to a faint yellow color, but the visual impression of Uncle Sam has been variously described as white or slight pink. Judging from the color, the diamond is most likely of pure IIa diamond type
Diamond type
Diamond type is a method of scientifically classifying diamonds by the level and type of their chemical impurities. Diamonds are separated into four types: Type Ia, Type Ib, Type IIa, and Type IIb...
meaning the amount of impurities is below a few parts per million. The clarity
Diamond clarity
Diamond clarity is a quality of diamonds relating to the existence and visual appearance of internal characteristics of a diamond called inclusions, and surface defects called blemishes. Clarity is one of the four Cs of diamond grading, the others being carat, color, and cut...
of the stone was assessed as VVS1, which stands for Very Very Slightly Included and means the stone has minute non-diamond inclusions that are difficult for a skilled grader to see under 10x magnification.
The diamond was owned by the Peikin Jewelers of Fifth Avenue, New York
New York City
New York is the most populous city in the United States and the center of the New York Metropolitan Area, one of the most populous metropolitan areas in the world. New York exerts a significant impact upon global commerce, finance, media, art, fashion, research, technology, education, and...
. It was lent by Peikin to the American Museum of Natural History
American Museum of Natural History
The American Museum of Natural History , located on the Upper West Side of Manhattan in New York City, United States, is one of the largest and most celebrated museums in the world...
for temporary display and storage. In 1971 it was acquired by a Boston dealer, Sidney de Young, and sold for $150,000 to an anonymous private collector.
The discovery of Uncle Sam arguably rescued the Arkansas Diamond Corporation, which had a debt over US$276,470 by that time and was going to be shut down in the winter of 1924. The number of diamonds found on the surface was decreasing, and the cost of digging operations was estimated as higher than the expected diamond recovery. Not that the value of the diamond was sufficient to cover the debts, but the discovery lifted the spirits enough to keep the surface operations. Currently, the Crater of Diamonds State Park in Arkansas is the only public diamond mine in the world. Over 75,000 diamonds have been found here since the opening of the park in 1906. The place where Uncle Sam was discovered is marked, and many additional diamonds have been found there.
External links
- Images of the Uncle Sam diamond at the ThinkQuest online library.
- Another image of the Uncle Sam diamond at the Encyclopedia of Arkansas.