Early prospection efforts in North America relied heavily on the use of crucibles to test suspected valuable minerals ahead of their potential exploitation. This is well-known for metal ores, and has also been proposed for glassmaking at colonial Jamestown. Here, we revisit a recent publication proposing that certain Hessian crucibles from the site bore evidence for these glassmaking tests, and present new data on crucible operations at the site. We argue that the evidence is more consistent with testing ores for their precious metal content than with glass making. Despite this, the historical evidence for glassmaking tests in this early period remains strong, and further research may well identify its material remains.