A modification of a previous synthesis for the formation of GaAs nanocrystals is reported. Unlike the previous synthesis, the new procedure produces quantized GaAs colloids which do not also contain molecular species which interfere with the optical properties of the GaAs particles. The GaAs colloids have been characterized by transmission electron microscopy, electron diffraction, ultrafiltration, absorption and photoluminescence spectroscopy, and transient pumpprobe spectroscopy; these experiments indicate that the particles have a size ranging from 20 to 80 A