I was fooling around with the new microscope, taking some unimportant pieces from trips past to practice a bit of sewing needle prep. Back in the summer I had crossed the river at Arkona to check out the south banks for the first time. It was underwhelming as it looked pretty picked over, and exposures were too dangerous to access. I had noticed a pile of Widder shale that someone had obviously placed there - mostly broken bits and other stuff that would be somewhat decent for a first time collector. I make similar conspicuous piles for others of stuff that doesn't meet my standards, or of fossils I already have too many of. So the piece I was fiddling with is the light beige one on the far right, found on August 18th. You can see the impression of a full prone Greenops widderensis, as well as a busted up prone next to it - a classic piggy pile. Whoever got the other side probably felt pretty lucky. Although it was not a complete one, I put it in my collecting bucket anyway. My delightful discovery of a third Greenops on that slab I was working on back in late October (post here) taught me something: the rich yet very thin Greenops layer tends to have them in multiple assemblages. Fast forward to now. I figure why not take the chance to see if there are any more lurking under here? I think you know where this is going! I began chipping away at various spots and saw some thoracic segments sticking out beneath the broken cephalon in the centre. Over two hours of using the sewing needle, I continued chipping away. Under serious magnification, it gave me a great deal more precision in removing matrix. Yeah, the impression had to be sacrificed, but for the good cause of a full prone trilobite! I decided to keep the broken cephalon on the top to make it an interesting association piece. I also uncovered more of the head of the top one, and discovered a pyritized partial below it. The next step was abrasion under serious magnification (where a single segment might take up my entire field of view), followed by some more sewing needle work. Not too bad! It has a few problems (two right pygidial spike tips are broken, parts of it seem to be rolled underneath itself slightly, and the glabella got crushed during preservation), but I'm proud of this one. A last step may be to find a way of getting out the ugly tool marks. This is a comparison of where I began, and where it ended up. So, not as good as some of my more seasoned and experienced fossil preparators I know, but a good start where the right tools make a real difference.
I still have some other Widder shale from previous trips that were disappointments showing a full impression and little else, so perhaps I ought to have a closer look. Or, as my fossil comrade Malcolm says, I should go out and buy a lottery ticket. Comments are closed.
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Kane Faucher
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February 2024
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