Four different types of experimental planchets have been identified so far from 1999 State quarter dollars struck on blanks purportedly to have been tested for the Sacagawea dollar.
The latest example acquired by Michael S. Byers of Byers Numismatic Corp., Lake Forest, Calif., is a 1999-P Delaware quarter dollar that has the golden color of the Sacagawea dollar and the copper center core. Professional Coin Grading Service certified the coin as Mint State 63.
According to Byers, there are approximately 15 known 1999 State quarter dollars struck on experimental planchets. All five states are represented - Delaware, Pennsylvania, New Jersey, Georgia and Connecticut - with New Jersey represented by a single specimen.
All of the specimens identified are Philadelphia Mint strikes, since it was at the main U.S. Mint production facility that the majority of the experimental testing for the Sacagawea dollar took place.
Byers indicates that PCGS and Numismatic Guaranty Corporation of America have authenticated and certified at least one specimen to date.
Byers said the coins have been identified and classified by four types:
Type 1 - This type has the "color" of a Sacagawea dollar and has the copper center core.
Type 2 - This type has the "color" of the Sacagawea dollar but does not have the copper center core.
Type 3 - This type has a slightly "green" color and has the copper center core.
Type 4 - This type has a slightly "green" color but does not have the copper core.
"These coins were analyzed by scanning electron microscopy with energy-dispersive x-ray spectroscopy (SEM-EDX) to determine alloy composition," according to Byers. "The predominant metal is copper, followed by zinc. There are also small percentages of manganese and nickel."
The adopted composition for the Sacagawea dollar consists of the alloy layers on each side of the center copper core of manganese-brass, a golden-colored alloy composed of 77 percent copper, 12 percent zinc, 7 percent manganese and 4 percent nickel.
Taking into account the copper core, the overall composition of the dollar is 88.5 percent copper, 6 percent zinc, 3.5 percent manganese, and 2 percent nickel.
"In a recent Freedom of Information Act (FOIA) request for copies of any reports and test results, the Department of the Treasury acknowledged that 'the U.S. Mint conducted engineering and metallurgical tests as part of its development of an alloy for the Golden dollar,' but would not release any information," Byers said.
Byers noted the experimental State quarters have sold for as high as $10,000 each, depending on which state, the coin's condition and which type of experimental composition was used.
Byers outlined diagnostics to determine if you have discovered in circulation a State quarter on an experimental planchet:
Weight - The weight on all of these discovered so far is overweight for a dollar, varying from 5.9 grams to 6.3 grams. The adopted weight for the Sacagawea dollars is 5.67 grams.
Size - It is slightly thicker than a regular State quarter dollar, due to the heavier planchet.
Color - So far, the pieces discovered are either the same "color" of the Sacagawea dollar or have a slight "green hue" to them.
Look - The edge is slightly rough and may have a higher rim around part of the edge.
Edge - Some of these do not have the center copper core.
Strike - None discovered so far are proof-like in the fields.
Reeding - Some of these have incomplete reeding.
For more information or to view the latest discovery, go to Byers' Web site at www.byersnc.com. Byers can be reached at Michael S. Byers/Byers Numismatic Corp., Box 687, Lake Forest CA 92609. Telephone (949) 859-3981.
