Prehistoric Hopewellian peoples of Ohio (ca. 150 B.C. – A.D. 400) produced fine geometric and representational art that played central roles in their social organization and religious practices. A 37 week, complete visual survey of nearly all major eastern United States collections of Ohio Hopewellian artifacts revealed that many of the 304 extant copper breastplates, celts, and headplates have on them the remains of artistic compositions previously undetected. The images resemble other Hopewellian and earlier Adena art in other media in their content and style, and include representations of leaders (humans, animal impersonators) in ceremonial dress and animals of the natural world. Previous physical and chemical studies of the art works, as well as taphonomic observations, suggested that the artistic compositions were certainly made by collage of various organic and inorganic materials and possibly by painting with at least ten minerals pigments.
This project successfully achieved its three goals: (1) to identify more exactly the nature of the materials used to create the imagery on copper; (2) to identify the artistic processes used to create the imagery; and (3) to develop a systematic, integrated set of digital photographic techniques for effectively recovering, enhancing, and displaying the art works on Hopewellian copper artifacts, as one approach to preserving the images and guiding their conservation. A team of eleven researchers, with specialties in archaeology, remote sensory systems, digital image photography and enhancement, applied metallurgy, mineralogy, petrology, paleoethnobotany, and prehistoric textile analysis carried out the project work.
This research was made possible through Grant MT-2210-0-NC-12 from the National Center for Preservation Technology and Training (NCPTT).