On the way back from Hastings Street in Noosa to our apartment we took a bit of a short-cut past the Sheraton Hotel. The elevated walkway outside the hotel is paved with a finely bedded arenite (sandstone for the non-geologist) with what looks like a spaced cleavage imparting something of a phyllitic appearance to the rock. One or two of the slabs display excellent fine dendritic features. Dendrites, named after the Greek word for tree, dendron, may be readily mistaken for fossils but are in fact a mineral growth along a narrow fracture in the rock. The best dendrites are usually composed of manganese oxides such as pyrolusite as seems to be the case with this one. Click on the photo for an enlargement.