FIG. 1 is a right side perspective view of a lava lamp holder showing my new design; FIG. 2 is a front view thereof, a rear view being a mirror image thereof; FIG. 3 is a left side elevational view thereof; FIG. 4 is a right side elevational view thereof; FIG. 5 is a top plan elevational view thereof; and, FIG. 6 is a bottom plan elevational view thereof.