[1] In 1851, Cloez and Italian chemist Stanislao Cannizzaro, working on collaborative research, prepared cyanamide by the action of ammonia on cyanogen chloride in ethereal solution.
In the 1870s, he commenced the identification of the constituents of individual essential oils and their classification into groups according to their suitability for medicinal, industrial and perfumery purposes.
[2] He identified the major constituent of eucalyptus oil, which he called "eucalyptol" (now generally known as cineole).
[3] Cloez also played a role in developing a theory on the origin of life elsewhere in the Solar System.
[4] In 1864, Cloez was the first scientist to examine a carbonaceous chondrite, the Orgueil meteorite, after it had fallen in France.