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I'm not a brachiopod specialist by any means but have gradually acquired quite a few Carboniferous ones, both found and bought, and I'd like to start a thread for some of the more interesting (IMO) specimens that have hooked me into trying to learn more. The IDs are often traditional so I'd welcome any input from more knowledgeable folk such as Adam @Tidgy's Dad. As usual, detailed information is scattered around many journals. I'll start with a pair of Spirifer striatus recently acquired from an old collection. It's notable for its size, these being typical. The second partial specimen shows a crystal covered brachidium, rather broken up before mineralisation. Mississippian, probably Asbian Stage, Derbyshire, England The species is an old but valid one, Martin (1793), and these are from the same area as his type specimens. (There's a similarly large US species, S.logani, that I've been shown from the Keokuk Limestone of Missouri. I couldn't find any on the forum though.) specimen 2, with brachidium

I collected this brachiopod showing part of the brachidium yesterday - quite rare to see in this area. It's partially silicified and I was thinking of perhaps etching it out a little further. It's also a good geopetal example, with sediment in the bottom (graded if you look closely), the remaining void above being filled with calcite that has helped preserve the brachidium. On checking my photos, I realised that there were some nice clear foraminifera, about 1mm across, which I haven't really noticed much before from this limestone. These photos are just of the rough surface, taken just submerged which reduces the surface bumpiness and allows better contrast (much better than just wetting it). I think I've managed to identify the two(?) types shown here though I'm very happy to be corrected! There are many more in there and I'm going to cut and polish some of it. Great Limestone, Pendleian, upper Mississippian. Weardale, Co. Durham, England. Scale in mm. (The first Endothyranopsis is at the top near the rule, and another is halfway between the 10 and the rock edge. See blowups below.) ?Endothyranopsis sp. The white blob to the left of the obvious specimen may be the same species seen at right angles to it. Palaeotextulariid - I looked at a few genera of these and they're hard to distinguish from each other in a random section. More palaeotextulariids - at least two specimens Another ?Endothyranopsis sp. (actually on the reverse of the rock). General view - it might be zoomable to see various forams and bits - this is how I was looking for them and it seemed to be easier than with my x20 binocular microscope. Some good burrows showing up as well, especially in the bottom half. Finally, a view under water of the brachiopod - shows some quite jazzy calcite around the brachidium. I'm not sure if there's more than one loop here or just crystals growing out from a loop axis. Sparry calcite in the middle.