Some face paint cakes like Kryolan are hand-poured and may have lines or blemishes on the surface. Certain brands like PartyXplosion might develop cracks on the surface due to weather, like heat and humidity and varies from cake to cake. Due to their special formulation, pearl or neon colors could be more sticky or soft under these temperature and weather conditions.
Please be assured that any such blemish, crack or line on the cake is not an indication of age or quality. Such cakes can be moistened and used as a usual without any effect on performance.