The Plaster series consists of two overlapping iron plates, 3mm thick, with indirect light. The rear plate is decorated with gold or silver leaf as desired, wile the front plate is naturally rusted by means of wetting and drying cycles outdoors for more than 21 days. This means that, with each lot of iron slabs, depending on the percentage of lead and steel contained in the same slabs, the final color of the rust may vary. This change is therefore from to be considered a particularity of the lamp and not a defect of production.