Schunck also studied at Berlin under Heinrich Gustav Magnus (1802–1870) who published over 80 papers on many diverse topics in chemistry and physics.

It was from Gießen that in 1841 he published his first research paper, in Liebig's famous journal Annalen der Chemie.

After disengagement of gas has ceased, water is added to the residue, which forms a precipitate – the chrysammic acid.

By the 1830s the researches of Pierre Jean Robiquet (1780–1840), Friedrich Heeren (1803–1885), Jean-Baptiste Dumas and Robert John Kane (1809–1890) into the constituents of lichens had revealed three colour precursors: orcinol, erythrin and pseudoerythrin, but their constitution was not precisely known.

Liebig encouraged Schunck to reinvestigate the subject using dye-producing lichens that grow on the basalt rocks of the Vogelsberg in Upper Hessia.

Rubian was an uncrystallisable gum, hydrolysable by acids or an enzyme contained in the madder root to give alizarin and a sugar.

Rubian was actually a mixture of glycosides of di and trihydroxy anthraquinones of which a major component was ruberythric acid which is an alizarin 2–b–primeveroside.

Many other "compounds" derived from the hydrolysis of rubian were described and enthusiastically named by Schunck: rubiretin, verantin, rubiacin, rubiadin, rubiapin, rubiafin and others, but some of these are most likely to be impure alizarin, and best forgotten.

Believing that the occurrence of indigo was more common than generally supposed at the time, he examined the urine of 40 individuals, all apparently healthy, with ages between 7 and 55 years, mostly of the working class.

He thought this variation might be due to different kinds of diet, but after many experiments, found only one which worked: "I took on the next night, before going to bed, a mixture of treacle and arrowroot boiled with water in as large a quantity as the stomach could bear, and the effect was that the urine of the following night gave a large quantity of indigo-blue".

[5][6][7] Schunck built a private laboratory in the grounds of his home, "The Oaklands", in Kersal, which together with his library and collection of specimens were bequeathed to the Victoria University of Manchester.

His books are now in the John Rylands University Library[9] and his specimens in the Museum of Science and Industry in Manchester.