The macroscopic behaviour of minerals is not always directly related to their crystalline structure at the atomic scale but often depends explicitly on mesoscopic (nanometer–micrometer) features. This paper reviews various cases where the macroscopic phenomena differ from those of the bulk, with structural and chemical variations related to: domain walls, leading to enhanced or reduced transport properties; surfaces controlling growth morphologies; and radiation-damaged minerals where the interface between the amorphous and crystalline phase is believed to play a key role in hydrothermal leaching behaviour. Minerals explicitly discussed are: quartz, agate, hydroxylapatite, cordierite and metamict zircon.