Rattlesnake Cave is located on the western shore of Lake Abert in the northern Great Basin of southeast Oregon, one of hundreds of archaeological sites in the Lake Abert/Chewaucan Basin. The site was dug by collectors in the 1950s, and recovered materials were donated to the Fort Rock Valley Historical Society and Homestead Museum in the early 1990s. We analyze 77 artifacts in the assemblage, which includes cordage, basketry, moccasins, as well as wood, bone, and stone tools. We report new radiocarbon (14C) dates for the site, and the results of energy dispersive x-ray fluorescence (EDXRF) on one basalt and nine obsidian bifaces, matching their chemical signatures to regional geologic sources. We discuss the place of Rattlesnake Cave in the broader context of the northern Great Basin while demonstrating how museum collections may contribute to addressing anthropological research questions.