This frog was cast in a single pour from a tumbaga alloy of gold and copper; the flat feet may have been further thinned and shaped by hammering after casting. Silver in a quantity of 1% was not an intentional addition but more likely present as an impurity in the gold. Pendants from this region were typically surface enriched with gold, but this frog’s copper color may indicate that there was little or no surface enrichment. X-radiography was used to investigate the condition of the frog. A small repair is visible along the mid-section indicating difficulties with the metal flow during casting. The dark spots in the x-ray result from trapped gas bubbles present as the molten metal cooled down. These porosities make the object weak and susceptible to breakage.
- Exploring Art of the Ancient Americas: The John Bourne Collection Gift. The Walters Art Museum, Baltimore; Frist Center for the Visual Arts, Nashville. 2012-2013.
- Gold of the Ancient Americas. The Walters Art Museum, Baltimore. 2015.