Porphyrit-Hornstein Formation
Stratigraphic range: Ladinian ~242–235 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Type	Formation
Unit of	Becici Group
Location
Coordinates	42°30′N 18°54′E / 42.5°N 18.9°E / 42.5; 18.9
Approximate paleocoordinates	2°06′N 25°18′E / 2.1°N 25.3°E / 2.1; 25.3
Country	Montenegro
Porphyrit-Hornstein Formation (Montenegro)

The Porphyrit-Hornstein Formation is a geologic formation in Montenegro. It preserves bivalve fossils dating back to the Ladinian of the Triassic period.^[1]

The following fossils were reported from the formation:^[1][2]

• Bivalves
  • Ostreida
    • Halobiidae
      • Daonella (Arzelella) indica
      • Daonella (Pichlerella) pichleri

• List of fossiliferous stratigraphic units in Montenegro

• Schatz, W (2001), "Revision der Untergattung Daonella (Pichlerella) (Bivalvia, Ladin)", Eclogae Geologicae Helvetiae, 94: 389–398