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In October of 2021 I made a 4 day trip to the Marble Mountains of Southern California to look for trilobites. The order of note is Redlichiida. The biggest percentage is Olenellus followed by Bristolia then Mesonacis. The vast majority of finds are just cephalons followed by thorax pieces. Last year I hunted here about 8 days. I probably found over 400 cephalons (could be a way higher) but only 2 completes with 3 maybe's as there are buried. With all that I've only found 1 pygidium on its own. There are a few other fossils to be found at the site. A couple brachiopods, a hyolith, and a few other invertebrates along with trace fossils are also among the possible finds When I'm visiting family in Arizona this is my new go to spot..... mostly because it is the closest with trilobites (which of course are the best fossils out there ) It takes me about 6 hours to drive there so it makes sense to spend some time on the site. I usually end up hunting well into the night to make my time count. There are a few sights to see along the way as well, the Amboy Volcano National Monument and the ghost town of Amboy. Both are along the Historic Route 66. Scale shown in the specimen photos is: little marks are 2mm and the numbers are cm Amboy sunrise The site is near the old town of Cadiz. Here is a sign near the turnoff for the site. Once onsite you have to pick a spot and start digging. There is about 2ft of very broken and fragmented shale overburden to deal with (between the red lines) Bring a mask! This stuff kicks up a TON of dust and it's not really that healthy to breath in. This spot has been know for decades and as such the overburden from the upper digs is burying the lower sections. Would be nice if we were allowed to bring in some bigger gear to remove a lot of it to make accessing the lower areas practical. But, being on BLM land, only regular hand tools allowed. After picking my spot to play, and digging the overburden out of the way, it was time to break rock. My spot for the next 4 days So, as I stated, the vast majority of finds are lone cephalons. They range in size from a couple mm to over 10cm! Unfortunately the large ones are so hard to find intact. With the rock being so fragile / fragmented sometimes they are in dozens of tiny pieces making it about impossible to fix. So, you keep digging and splitting to find more. Mesonacis fremonti cephalon And, sometimes the preservation is weird or just awful And then you find a nice large cephalon that isn't broken (and stays that way when you try to remove it) Olenellus nevadensis cephalon (I think) One of the best large ones I've found yet. There are quite a few smaller ones to be found in decent shape. Sometimes they are really little if you keep you eyes open Olenellus clarki cephalon (I think. The smaller ones are harder to tell for me as I have not found a good reference) Sometimes you get lucky and find a multi plate with nice examples I believe this is a Olenellus double (not quite sure of species yet but it appears to be 2 different species. I really like this multi. 4 individuals all right side up. It appears to be 3 Olenellus clarki and one I haven't ID'd yet (still wrapped from travel) Double Olenellus clarki with one ventral and one dorsal (positive and negative) My only pygidium after looking at thousands of trilo - bits It appears that when they molt that the parts are barely held together. As such they tend to fall apart quickly. That is part of the theory as to why so few completes are found here. As such I did find this large thorax section. I'm hopeful that the rest is buried but it doesn't look promising (positive and negative) But after 8 total days of digging I only have a few complete. Most are partial buried. BUT, I finally found one that popped out just great! It's missing a tiny bit of cephalon but I can live with that. A little prep would uncover the hidden pleural. And maybe clean up the extra cephalon. Olenellus clarki Since this is my closest accessible spot I'll keep going back. There are a number of other species I can still try and locate complete ones, or at least nice cephalons of the different species. My dream is a large complete one. And now that you have (or I have in this case) collected your finds a word of note: since this is US government land you are allowed to collect BUT no selling or trading of specimens. You may give them away but no compensation. Speaking of this, in the future I will have some to give out once I figure what I've got and pull out my keepers. There is more to come but my computer and the internet aren't talking well at the moment so I can't download more photos. To Be continued