The chair was crafted using traditional carpentry techniques (saw, chisel, and plane). It's made of over fifty-year-old spruce. The wood has been twice treated with the traditional japanese tanning technique (yakisugi). The surface is hand-polished. Additionally, the wood has been impregnated with the highest quality tung oil. The detail is made of ebony. The fittings are made of steel. The chair's proportions are based on the fibonacci spiral. Designed by a master of arts (sadovsky de sa de). Signature. This piece has an attribution mark, i am sure that it is completely authentic and take full responsibility for any authenticity issues arising from misattribution