Bertoia's series of sculptures of welded natural works began in the 1960s: metal bushes, shrubs, dandelion flowers, weeping willows, mushrooms, bundles of hay and wheat sheaves were created. Presumably it is the thought of a mushroom shape that bertoia captures in the sketch. In minimalist simplification, he draws the spherical formations in the lower half of the leaf and thus indicates the rather flat shape of the whole. The figures of his organic sculptures made of forged copper and bronze seem to be based on this drawing. untitled (mushroom), ca. 1960 black ink on strathmore-velin h 21 w 27.8 (excl. Frame) with certificate of authenticity of the estate harry bertoia by celia bertoia, utah, 01.06.2022 (in copy). provenance rago auctions, lambertville, auction 05/18/2022, lot 255 henning lohner collection, berlin 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