The purpose of this research work is a presentation of Jurassic limestones of the »Ammonitico Rosso« type, outcropping in the area of Mežica (Jesenikov vrh) and Mt. Uršlja gora and the presentation of the fossil material, that was found there by private collectors Ivan Ocepek and Matija Križnar. Samples were collected at the sites and thin sections were made in order to determine the microfacies. The ammonites that were determined at Jesenikov vrh are Psiloceras neurtigense, Lytoceras cf. cornucopisa, Harpoceras sp., Phylloceras sp., Hildoceras subserpentinium, Phylloceras heterohyllun, Dactylioceras cf. commune, Phlyseogrammoceras cf. dispansum, Fucinicera amalthe, Holcophylloceras calypso, Liparoceras sp., Paroniceras sternale, Hyperderoceras planarmatum, Hildoceras cf. sublevisioni, Hammatoceras speciosum, Hammatoceras speciosum, Arieticeras cf. retrorsicosta and Arietites sp. The assemblage suggests Toarcian age. The microfacies types are bioclastic packstone and crinoid rudstone/floatstone. Under Uršlja gora the microfacies types bioclastic wackestone and bioclastic packstone were determined. The microfacies types suggest deposition in a deeper marine setting. In the limestone from locality Uršlja gora planktonic foraminifera were found, suggesting Middle Jurassic age. The time of sedimentation of the red nodular limestones is thus determined to be at least from the Toarcian to the Middle Jurassic.
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