The awareness in recent years that chemistry needs to become more sustainable, green, and cost effective has resulted in growing interest in mechanochemical methods. IUPAC in 2019 acknowledged mechanochemistry as one of the top ten emerging technologies in chemistry which will contribute to the well-being of society and the sustainability of planet Earth. We report here results that illustrate the power of ball grinding to discover and stabilize new, otherwise inaccessible polymorphs, and that shed light on the factors that lead to nanocrystalline polymorph stabilization.