It turns out that reports of whole sponges were entirely accurate, and strange things they were too. The first sign was bubbly black markings in the mudstone that stand out much better when wet (convenient, that). We've not yet found a whole one, but I reckon the entire thing was probably a good 10 cm long... which for the earliest Ordovician (Tremadoc) is quite unusual. The black preservation is some oxidation product of pyrite (we found one or two fresh ones as well).
There were other sponges as well, including this amazing little thing, a mere centimetre or so across. The stalk is like nothing I've ever seen on a fossil before, although I'm sure there are some recent ones that are fairly similar...
The object of this trip was to investigate a possible field site for our reseach over the next couple of years. I reckon it passes the test... we can't wait to get back.
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