Mannenjak van blauw geverfd katoen en een voering van wit katoen. De voering is deels over de kraag genaaid voor een wit accent. Aan beide zijden van het voorpand zitten sluitbanden waarmee het jak wordt dichtgeknoopt. This is a typical jacket, chŏgori in Korean, made of cotton for men. After cotton was introduced in Korea in the late 13th century, cotton culture flourished and cotton cloth became popular. The weaving of cotton cloth began with the cultivation of cotton plants and the harvesting of cotton bolls, and involved many subsequent steps such as carding to remove the seeds and spinning the cotton fibers into thread for weaving. The best quality cloth was made with 15- to 2l-ply thread, while cloth for commoners was made with 5- to 8-ply thread. This chŏgori shows traces of indigo dyes. Making indigo dye begins with cutting the plants in the early morning before the summer sun dries up the dew. The plants are stored in a jar and turned over exactly 24 hours later. Oyster shells are burned on a pile of wood, covered by straw mars, and then pulverized, sieved and added to the water containing indigo. As the oyster powder is stirred into the jar, the indigo juice changes from yellow to jade green to green to blue, and froth rises like a cloud. At the end of the oxidation reduction process, the indigo settles to the bottom of the jar and jells. The jelly is saved and diluted in water in another jar with wood ash being added. The jar is kept in a room while the solution seasons into dye. It needs a delicate skill to balance of ingredients and conditions involved in the oxidation reduction process. During this process if stirring by a wooden rake or scoop is not even, colour is not permeated. If there is few froth found, dyeing is impossible. If the ratio of combination with the powder and water is not precisely even, decolourization would occur. This jeogori's colour might have been caused by one of the above reasons.