The story
The firm's heyday is considered to have been between 1839 and 1882. They published a wide range of material including book illustrations and lithographic sheet music covers. Their best work was in the field of large chromolithographs. Hanhart used a complex layering of tint stones, to produce work unique in colouration and tonal values.
From Wikipedia’s article on M. & N. Hanhart, shared under CC BY-SA 4.0.3
