Chert-bearing Oberalm Limestone (Oberalm-Schichten, Oberalmer Kalk; uppermost Jurassic/lowermost Cretaceous), with the chert being overgrown by the extant lichen <i><a href="//commons.wikimedia.org/wiki/Rhizocarpon_geographicum" title="Rhizocarpon geographicum">Rhizocarpon geographicum</a></i>, Wildgößl, Styria, Austria
<a href="//commons.wikimedia.org/wiki/User:Tigerente" title="User:Tigerente">User:Tigerente</a>
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<span class="int-own-work" lang="en">Own work</span>