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Mostly Mediosprifier with maybe the odd Mucrospirifer. Largest ones I've encountered compared to Arkona.

From the album:

Some Highlights from the PD weekend

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  • Taken with Apple iPad Air 2
  • Focal Length 3.3 mm
  • Exposure Time 1/198
  • f Aperture f/2.4
  • ISO Speed 25

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I was just at PD. Can you please post what tools you used and if you had any help. I spent three days there and didn't find very many whole trilobites (Phacops). Maybe I just have bad luck. I managed to recover some decent finds but certainly not as good or abundant as yours. I have been here a few times so my collection is decent, but I would like to expand it.

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Hi jsnrice!, 


I come to the site generally well prepared with good tools, but not so hardcore as bringing rock saws! :P I have an array of sledgehammers, cold chisels, pry bars, rock pick, brick hammer, and a mini shovel to remove overburden. The rest is just human power and stamina in cracking out big slabs from the lower Windom touching the waterline. In terms of help, that really depends. Sometimes it is concentrated removal to collaboratively clear an area and mark out where the slabs and domes are, and most other times I can generally manage it on my own if the slab to be extracted maxes out at 250 lbs. More than that might require a second hand to lever it and lift it out of the extraction zone for splitting. But once you hit in the higher weight, it isn't as manageable to work with. Ideally, a 2' x 3' x 1' slab will work best so as to avoid simply splitting at the edges leaving a thick chunk in the middle surrounded by sharp edges. I then take the sledge to give it some firm taps on the edge to exploit any unseen fracture lines caused by the presence of fossils. After that, it becomes a matter of using the chisel to split along those fracture lines.


Whole trilobites can be hit or miss - most times you find assemblages of broken moult bits, or trilo-bits in isolation. There are "lenses" of a sort in the strata, and it can be tricky to find them (and even if you follow a promising thin area, it may not continue as you proceed on the horizontal). I managed to find only about 3-4 full prones, but a lot of rollers in various states of completion. When I split a slab, I generally also look for what is along the edge: if I see a little cephalon poking out, I may try to split at that point to see if it is complete (or, if you're really lucky, opens up a whole death assemblage!). I'm finding that the "trilobite" pit is starting to run out of strata as people like us are working it right back against the walls of the dug-out pit itself. When Digging with the Experts happens next May, I presume they'll be expanding or digging out a whole new area for us to work on. I also found some areas in the pit contained more concentrations of Greenops, too. But for every ton of rock, you might be lucky to find a nice full prone Eldredgeops amidst a lot of rollers. Others like to focus on the spoils piles and can have some good luck on chunks discarded by others. I've had the most luck with the bottom inch just above the waterline, followed by 4-8" of either blank or chunky horn coral layers, and then another 1-2" of trilobite layer. 

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