Previous work on the properties of viscous remanent magnetization (VRM) have shown that it can play an important role in some paleomagnetic investigations. The results of this study on the properties of VRM of very fine, single-domain (SD) and coarse, multidomain (MD) magnetite particles ranging in size from 0.02 to 60 μm indicate that the MD samples are very sensitive to the previous magnetic history of the samples. The af demagnetization causes a dramatic decrease in the ability of MD samples to acquire VRM compared to the same sample with an undemagnetized thermal remanent magnetization (TRM). Thermal demagnetization of the same MD samples causes an increase in the ability to acquire VRM components. Submicron SD samples show VRM acquisition and decay cures that are independent of previous magnetic treatment. Both MD and SD samples are extremely sensitive to the length of time of zero and weak field storage that occurs prior to the application of the external VRM field. A model using the total energy of the system is used to describe the above results.