AMERICAN JOURNAL OF UNDERGRADUATE RESEARCH VOL. 1 NO. 1 (2002) Chemical Compositions of African Trade Bracelets (Manillas) via Energy Dispersive X-Ray Fluorescence Mike Kuntz, Jennifer Ferguson, Vincent Iduma, Renee Kuzava, and Mark Benvenuto Department of Chemistry and Biochemistry University of Detroit Mercy 4001 W. McNichols Road Detroit, Michigan 48219-0900 USA Received March 4, 2002 Accepted March 13, 2002 ABSTRACT Sixteen small, west African trade bracelets called manillas, and one large, African trade bracelet referred to as a king manilla based on its size, were analyzed via energy dispersive x-ray fluorescence spectrometry and compared for the following elements: copper, zinc, tin, lead, antimony, and arsenic. The composition of the bracelets varied widely in the amount of lead present, especially when compared to the official amounts of lead allowed by the various manufacturing concerns. The king manilla showed a markedly different chemistry than the sixteen smaller manillas, consistent with the belief such large manillas were not manufactured in the same location as the small. I. INTRODUCTION Copper objects have been traded as items of money and wealth in sub-Saharan Africa for hundreds of years [1]. European trading companies produced millions of copper bracelets, known as manillas, for use in west African trade; and their use continued in many areas well into the twentieth century [1]. While these items have been of interest to and have been studied by numismatists who specialize in non-traditional forms of money, they seem not to have been studied in terms of their metallurgical composition, perhaps because early, published reports simply have stated what their compositions should be [1-3]. Until this time, there appears to have been no attempt to determine the chemical make up of any sampling of these bracelets via a non-destructive, analytical chemical technique. The sixteen smaller bracelets analyzed here vary in size, as shown in photographs 1 – 16. In addition, there are certain differences in style, as can be seen most obviously when comparing photograph 16 to the others. The king manilla is considerably larger, as seen in photograph 17, being approximately 12" long. The bracelets have been matched to their type in the Opitz reference [1], and are listed in Table 1. Where possible, their presumed city, country, or region of manufacture, as well as possible dates of manufacture, are also listed. II. PROCEDURE Bracelets 1 – 10 were purchased for study, and bracelets 11 – 17 were provided as loans from the American Numismatic Association, headquartered in Colorado Springs, Colorado. Bracelets 1 – 10 were wiped with a Kimwipe prior to exposure to X- rays, while bracelets 11 – 17 were not cleaned in any way prior to exposure. [See the Appendix for photographs of the manillas.] 29