Sigmund Zois (1747-1819) was creator of Zois mineral collection.
He was well-educated owner of wholesale iron busyness and the
central personality of the Enlightenment in Slovenia. In the
world he is much better known as a great natural scientist,
primarily a mineralogist. He was good in mineralogy, chemistry,
metallurgy and mining as well as in botany and zoology. Among his
correspondents we can find such prominent names as Abraham
Gottlob Werner, professor of mineralogy at the famous Mining
College in Freiberg, Martin Heinrich Klaproth, professor of
chemistry at the University of Berlin, Peter Jordan, a professor
of natural sciences at the Medical faculty of the University of
Vienna, and the mineralogist Friedrich Mohs, known for his
introduction of the hardness scale into mineralogy. His
contemporaries held him in great esteem, which is evident from
the acknowledgements bestowed upon him by renowned institutions:
Gesellschaft naturforschender Freunde zu Berlin (1782),
Imperialis Leopoldino-Carolina Academia Naturae Curiosum,
Erlangen (1793), Academie Celtique, Paris (1806), Jenaer
herzoglich = mineralogische Sozietät (1807), Wetterau'sche
Gesellschaft für Naturkunde zu Hanau (1808). In 1805 a new
mineral was named zoisite in honour of Sigmund Zois. Zois was
awarded a high state decoration; namely the Commander's Cross of
Leopold's Order (1809). He took great pains for Carniolia to get
its own provincial museum. Though Zois did not live long enough
to see it, soon after his death his collection of minerals became
a foundation stone of the Provincial Museum in Ljubljana (founded
When in 1804 the mineral dealer, Simon Preern, provided Zois
with specimens from Saualpe Mountains in Carinthia, Zois
recognised a new up till then unknown mineral. The letters from
A. G. Werner and M. H. Klaproth confirmed this fact. In 1805 A.
G. Werner, in accordance with M. H. Klaproth and D. L. G.
Karsten, named this mineral after Sigmund Zois, zoisite.
Nowadays, the type locality of zoisite is precisely determined:
Prickler Halt on the western slope of the Saualpe Mountains in
Carinthia. The area with a quarry abandoned a long time ago
consists of eclogite being cut by zoisite bearing pegmatite dike.
Zoisite is a common mineral in regional metamorphosed rocks, but
mostly represented in fine-grained aggregates. Reddish varieties
are called thulite. Bluish zoisite crystals, which were found in
Tanzania, are called tanzanite and are valuable precious stones.