I'm on my Easter break at a friends house in Tuscany, Italy and they have this stone on there terrace with what looks like small fossils on it. They must have had it some years now and not paid much attention to these markings... I thought I would try to find out what they were. The store is sandstone but it looks like there was a clay lair where the fossils are. ??? Any Ideas?
Ignoring the veins and fissures, most of the features are trace fossils, mainly horizontal and vertical burrows.
There is/was a fair range of invertebrates responsible for these sorts of marks.
There are plenty of trace fossils in the Dolomites - a Google image search gives an idea of the range of morphologies