Jewellery enamels in powder form have a limited shelf life. High humidity and temperature can attack the enamel powder and may finally have a negative impact on the fired enamel decoration. The storage of jewellery enamels in powder form should not exceed 12 months. Under difficult storage conditions, e.g. high temperature, high temperature variations and high humidity we recommend using enamel lumps instead of powder. Enamel lumps are much more resistant and can be processed with hardly any loss of quality even after a long storage time.