An 18th-century costume in the Finnish National Museum's ethnographical collection is made from cod fish skin, measuring 70x35 cm, it was in a very dry, shrunk and crumpled condition. The stages of treatment were unfolding (after humidification), cleaning, softening (3 separate phases) then stretching of small areas at a time. The finished length was 1.15 m and the fish-skin was as soft as silk. As a support, coloured crepeline was sewn onto the reverse side of the costume, using catgut along the seams and 2-ply waxed silk thread along the edges. Loose edges were attached to the support with 15% pva in chloroform. Earth pigments in pva were used in retouching. The treatment took 1 1/2 years. The costume had been decorated with coloured fish scales sewn on with silk thread.