The heavy minerals identified in this study indicate that the sediments of the Harrison formation were derived from mixed sources and from reworked sediments originally deposited W. of the study area. Easily weathered unstable minerals are rare or absent. No significant heavy mineral zonations of the Harrison formation are evident from this study. Daemonelix forms were found in the lower portion of the Harrison formation at its type locality where they have heretofore been recognized only in the upper portion of the formation. The use of bromoform facilitates heavy mineral separation because it is easily frozen, and heavy mineral concentrations can be readily trapped by freezing the lower end of a test tube in which the separation has been made. The floating light minerals and unfrozen bromoform can be decanted, leaving a clean heavy mineral concentrate.