Chemistry Professor Gene Hall’s crowded laboratory in Piscataway recently overflowed with philatelic experts and news reporters witnessing a tension-filled moment in the world of stamp collecting. Hall’s expertise had been enlisted to help gauge the authenticity of rare, 19th-century Hawaiian postage stamps reputed to be worth millions.
Over and above his professorial undertakings, Hall is widely known as “The Paper Document Detective,” the go-to guy when there are problems in conservation and reconstruction of written or printed materials, or suspicions of counterfeiting.
Hall employed sophisticated analytical instruments to examine 10 “Hawaiian missionary” stamps that are part of a set that have been the focus of controversy since their discovery in 1918. The stamps, printed between 1851 and 1859 by the fledgling postal service of the independent Kingdom of Hawaii, were used primarily on letters sent home by Christian missionaries working in the islands.
The 10 stamps submitted to Hall for analysis are part of a group allegedly found in 1918 by George Grinnell, a Los Angeles collector, who sold some that were subsequently said to be forgeries. Grinnell lost the ensuing lawsuit and refunded the money. Ever since, Grinnell and his descendents have battled to establish the authenticity of the stamps and clear his name. Hall’s 10 are reputed to be fresh “Grinnells” that recently resurfaced.
Wilson Hulme, curator of the Smithsonian National Postal Museum, stood in the background last month as Hall used his high-tech tools to compare the newly found stamps to genuine missionary stamps Hulme had brought from Washington for comparison. In all, about 200 Hawaiian missionary stamps have been certified as genuine.
Hall produced chemical fingerprints of the inks used in the stamps and cancellation marks, and the chemicals present in the paper. He employed X-ray fluorescence spectroscopy to determine the elements present, followed by laser-based Raman spectroscopy to identify the compounds in which they occurred.
Two of the 13-cent stamps Hall tested showed the presence of mercury sulfide in the red ink, and iron and barium sulfate in the Prussian blue ink, consistent with what was used in stamps 150 years ago. On one of the two he concluded were genuine, he found the cancellation mark strangely containing telltale traces of zinc, barium and lead, not to be found in historic inks. A forger had apparently thought to “improve” the stamp with a bogus cancellation mark. The other eight in the group, he said, “continue to be suspect.”
Hall has a history of working with old and precious materials. When the rare, scientific manuscript the Archimedes Palimpsest was found, Hall was instrumental in its resurrection. The manuscript had begun life in the late-10th century as a parchment folio containing seven or more treatises by the ancient Greek mathematician Archimedes. Early in 13th century, monks short of parchment scraped off much of the Archimedian writing and overwrote it with prayers. Hall used the technique of X-ray fluorescence imaging to help make the original writing once again legible.