New life could be breathed into those stalwarts of filtering, the zeolites, thanks to University of Minnesota chemical engineer Michael Tsapatsis and his colleagues. Zeolites are commonly used in aquarium filters and as ion-exchange agents in laundry detergents. However, their economic impact is much wider as they are the key to cracking new petroleum products on an industrial scale. Tsapatisis and his colleagues have the past year monitoring the growth of zeolites in a laboratory setting to give them a clearer picture of the crystallization process. Their studies will ultimately allow them to develop, validate and improve a quantitative mathematical model describe such complex systems with a view to creating designer zeolites and related materials with highly specific and so efficient catalytic properties.