Septarian Jasper cabochon set in Sterling Silver
Septarian Jasper forms in nodules by a 'mineral cement' filling the porosity of sedimentary rock. Concretions are commonly composed of Calcite, Chert, Flint, Jasper, Goethite and Hematite. ... Septarian usually contain crystals precipitated from circulating solutions, usually of Calcite, Siderite or Pyrite.