Driven by the need to prevent crystallization of normal alkanes from diesel fuels in cold climates, the petroleum industry has developed additives to slow the growth of these crystals and alter their morphology. While the utility of such additives has been proven at the operational level, few studies have directly monitored their effect at microscopic scales. Here, we present a study of such additives in model n-alkane systems. We find a dramatic effect on the growth morphology: rather than the usual plate-like growth exhibited by pure wax, we see highly branched microcrystalline meshes. Under certain conditions, these meshes form well-defined bands with spacings larger than 200 mum. We suggest that successive bands form by nucleation via a metastable phase ahead of the inhibited growth front. (C) 2004 Elsevier B.V. All rights reserved.