Hydron blue G and R, patented paste 20% and powder
A dyer's sample book issued in 1911 by the Cassella Color Company of New York to show textile trades the range of its Hydron blue G and R paste and powder dyes. The plates are mounted swatches — skeins of wound yarn, folded hanks, knitted and pile cloth — dyed in graded navies, indigos and near-blacks against cream card, with small numbers keyed to each recipe; useful as dark blue colour references, fibre textures and specimen-card layouts.
