ABSTBACT: In 19Î4, thıoHte wm detected for the first tim© to the aHupdolom* (Oa^) md In Urn Hafc tendoloniit (Öa^) of the MMle ZeçhaWnformattôn near Eschwege âJad Sontra, He§aia# It was confirmed by means of dHlifog, chemical sad geochemlc^ MvesttgaMtons that m& fluorite to t^ HaupWolomit to stratabouiidL It occurs both locally to the İmm af macroscopic dark layer» mé lenses of up to 0.5 m thtog« aess smä moréoften, as mmm up to 1MÖ m thldte # É cannot maçroscopleaJly be distingulslied from the greyMt wMte dolomite without fluorite because of the low OaF# content (less tton 10 %), The fluorite contents vary between 10 and 50% OaF^ in the dark black layers. Bpedal^mples may contain op to 80 ^ OaFfl. The to^k colour derlvespartly firona the Mac fluorite but to a. greater degree fram bitumons material. Fluolrte has also been detected to the stmttgraphically hlgber Plattendolomit (Oa.,) of the Letae-iert. ei z S, Outcrops and quarries near Sontoa have local contenta of 1=4 % OàF|É The macroscopic and microscopiö toterstratiflcâtton of fluorite and dolomite with clear layer textures ani the absence M hydrothermal fluorite and other minerals in veins of fissures are evidence for a synsedimentary formation of the fluorite to the Hauptdolomlt (Caf) and the Plattendolomit (Ga.5)# The Ha~ aptdolomit to thought to have developed during late diagenesîn. This should be valid for the flmorlte, too* SlmMow lagoons M a saliiar facles are thought to have been the depositional environment. The fluorite precipitated from the sea water», which ware apparently endlched to fluorine byerosion at the fluorine rich granite» of the Harz m©ıratato§# Warn Is the only obvious explaantion o fthe large amounts of fluorine m the Zechsteta dolomite, estimated at 5J? s l^fconnes €aFr