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I have just returned from a trip to Ohio where besides family events, I picked up some loose end trilobites collected over the last few years that I was reluctant to prep fully. @isotelus, tell your son that he did a magnificent job!!!!!!! My pride and joy first. Thaleops ovata from the Platteville Formation/ Ordovician of SW Wisconsin Not far behind is this trilobite that I hesitantly call Gabriceraurus mifflinensis. Unfortunately, I could not locate the missing genial spine. I am a bit confused on this one. Initially I had IDed it as Illaenus americana but after its prep, it appears to be T. ovata. What continues to confuse me is the lack of long genial spines like the first trilobite pictured. One is broken. So it is hard to say with it. But the other is just a non fractured nubbin. Finally an unknown trilobite from an unknown location. Unfortunately, it never got labeled which is not good considering my age related forgetfulness. @piranha IDed this as Calymene breviceps from the Waldron Shale!!!!!!

As promised (quite a while ago, I'm sorry!) Here are photos and prep notes Start - scope is a low power model, x10 and x30. I do most of my work on x30. The needles I scrape with are in pin vises, available at most hobby stores and online. I find sewing machine needles are thicker and stronger, and work well. I do sharpen them with my wet stone when they get dull! (Be careful, it is very easy to have adjusted to using a dull needle for the past hour, sharpen it up nicely, and then press to hard, damaging the fossil!) The tuna can is for rock dust and pieces, they go to the compost pile. I heat the fossils on low heat for 5 minutes. I try to get them just hot enough that I can still touch them. I think this drives out the water, but I know from experience that it makes the fossils harder and stronger. At least in Wheeler shale. I do this at the start, every time I wash the fossils, and if I take a break longer than a week. The next step is to flip the fossil over and use my utility knife to scrap/grind off any high spots on the back. It is important that the fossil not rock back and forth while I am working on it. 1 - This is looking like a Brachyaspidion microps, Swazey Springs is thick with them! Despite the nice shield of matrix that covered the trilobite the spine at the top rear of the Cephalon has been lost. Oh well. The rest of the fossil looks to be in nice shape. I am leaving the matrix on the axial rings for last as it protects the small spines that sometimes are there. It will be the last part I clean for that reason. Note the "good" and "bad" pictures. It is always best to work with the needle pointing away from the fossil. Sometimes this is not possible, but I try to do as much work "away" as I can. I try to clean the whole fossil a little each pass, rather then trying to clean one area completely. If you are wondering what the half circle is on prep 1, I mark all my finds in the field with a circle around the fossil and an "x" on the back. It makes them much easier to find if I drop one or forget exactly where I set it down! 2 - While clearly an Agnostid trilobite I am not yet ready to id it in any way. I did not realize it till I started working but the shell has exfoliated on the parts that are exposed. Normally I would work a few areas hard to id the fossil, and toss it (OK, mostly likely it would go into a box I donate to a local school), but as I started on this little project I will finish it. 3 - It was just too weathered! I broke this one in half after about 5 minutes of work. I tried to glue it back together, but that did not work. All told I put about 30 minutes into each of the fossils that survived. I see from the picture I need to do a little more work on the Brachy!