Archaeocidaris

[tqb]

Common I know but this is the best piece I've ever found, we usually just get individual plates and spines here.

Picked it up a few days ago in a dry stream bed, washed out of a shale parting in the Namurian Great Limestone, Durham.

There's not usually much in there and the shale is very fragile - I backed it with fibreglass before low power prepping with air pen and abrader, still dinged a plate though...

The longest spine is 8.5cm

Before:


Prepped (it could be tidied more but bits start blowing away...):

[Joe Botting]

Hmm... you call Archaeocidaris common, do you? Blimey. Perhaps it is in places, but I've never found it. This is an absolutely stunning bit of preservation, even though it's disarticulated. I can see why you'd have been happy to find that.

Saw some in China that someone else had found - several complete ones on a bedding plane. They're really beautiful things, and of course well worth hunting for in terms of their interest value as well. Given the preservation you've been getting, I'd have thought a complete specimen at that site is quite plausible...

[tqb]

Thanks, Joe! - I am of course fantasising about articulated bits but Archaeocidaris always seem to have fallen apart before anything else...

Multi-plates with complete ones are fabulous, the spines often appear to be interlocked for mutual support.

There are some layers of brachiopods with spines in place from this bed (Eomarginifera longispina) so there's hope - needs a good flood to loosen some more material

(Went back yesterday and found one bit of radiole and one plate impression...).

[pleecan (Peter Lee)]

Nice find Tarquin!! PL

[tqb]

Thanks, Peter!