Understanding formation mechanisms at the atomic scale is essential toward the rational design and synthesis of zeolites; still, it remains challenging because of the unknown atomic confi gurations of starting and intermediate species. K. Muraoka, Y. Sada, A. Shimojima, W. Chaikittisilp, and T. Okubo combine NMR techniques with high-throughput computational calculations to understand how atomic confi gurations change when CHA zeolite is crystallized from FAU zeolite. Despite their structural similarity, the conversion involves signifi cant atomic rearrangement, which can be explained by the substitution of Al for Si within their common structural building unit—a prism break.