I was tinkering around this rainy autumn morning at the prep bench. After finding and preparing that lovely pair of Greenops I found at Arkona (report here), I figured there wasn't much else to do with it. Aesthetically, it would have been nice if I could safely trim the rock down as the pair are clustered at one end of a larger slab. So, I figured I'd play around with exploring the rest of the rock, seeing if there was anything else on the bedding plane. While I was doing that, the rock broke at the far end. Fortunately, the pair of trilobites were unaffected as the split happened at the opposite end of the rock. But it was then that I spied the impression of a third Greenops! The first task was to glue the rock back as it had split across the contact point between the cephalon and the thorax. You can barely see the crack now, and it seems well stabilized. Once the glue dried, it was time to uncover a bit more. The pygidial spines were uncovered, and they seem to be in good shape. A close-up. There is some significant damage on this one. I've flipped the image to show the trilobite right side up. The right side is missing a piece of its cephalon, the eye, and the genal spine. Also, there are two missing segments on the right side of the thorax. The left is also in rough shape. I'm not sure if the genal spine is intact, and it is missing portions of at least five ribs on its thorax. So what is next? I'm going to have to learn how to do restoration, using grafting of pieces from some of my spare partials that I've collected in the past. For that I am going to need a good mix of glue, magnification, and patience. I'll update this post when I can get around to performing this surgical task! UPDATE: As I was poking around a bit more, a nautiloid joined the party. It came flaking off, so I had to glue him back down. I also had some time to prepare an Eldredgeops rana roller I found at Penn Dixie earlier this month. Once I pried it out of the matrix, here it is in all its dusty, caked glory. This won't be simply a good scrubbing, but will take a mix of needles, air abrasion, and a special solution for softening the tough and stubborn matrix.
So I used the Paasche air eraser at 20-30 PSI, using 40 micron dolomite, for about 30 minutes. That, and other finishing touches, this one is nearly flawless. Have a look at the detailed pictures below: And this is where this fantastic, whirlwind, whistle-stop tour comes to an end: at the St Marys Cement quarry in Bowmanville. This quarry is massive, and it only opens up to collectors once or twice a year - and in that case, only to collectors who are part of a recognized club (and so Deb and I are new members of the Scarborough gem and mineral club). Safety is paramount at any quarry, and this one is no exception. Full safety gear is just the minimum, for there are plenty of other safety policies we are obliged to follow. We all assiduously follow all the rules as we want to maintain goodwill with the quarry owner. Violating safety is not only dumb and dangerous, but it risks collectors being entirely shut out from there forever. And so we began gathering in the parking lot around 8 am. The quarry is known for producing a lot of Isotelus and Pseudogygites trilobites. The workers see some of these big creatures going up the conveyor to be crushed to make cement and call them "turtles." And these trilobites can get pretty massive. This is how my day started. We had planned on just driving up to a hotel in Bowmanville, but they were all booked up. The one time I didn't book in advance since I figured, heck, it's Bowmanville... How hard could it be to find a place for the night? Famous last words! Fortunately, the kind staff at the local hotel called around and we got a place just 14 km up the road in Oshawa. The picture above is a brand new day as we are leaving the hotel to join our collecting comrades at the quarry. This is our crew eagerly awaiting entry. Our trip leader, Kevin, said that this must have been the biggest turnout for a day at Bowmanville. Weather may also have something to do with it: usually without fail the trip occurs when it is cold, rainy, or both. On this day, it was warm and sunny. This is a serious quarry. That truck on the right has tires taller than me! Once we signed our forms and had the safety talk from the quarry foreman, we formed a convoy of cars and entered the quarry. This quarry is so large that you actually do have to drive from one blast pile to the next. Many of us started at level 3. Those piles aren't tiny, and you are scrambling up piles of rock that can in some cases be the size of small apartment buildings. Yours truly giving closer inspection at a low-lying pile. Scale is tough to make out in this picture, but that wall in the background is probably about 300 or so metres away. The "trick" at this quarry is not to stay in one place to split rock, but to cover a lot of ground. About three of our crew have rock saws, and so what you do when you find a great specimen in some car-sized slab of rock is to mark it with tape so that at the end of the day the guys with saws can cut it out for you. My first find of the day: a beat up Flexicalymene. The stratigraphy of the quarry has a lot to offer. At the very bottom is the Verulam Formation (the dominant unit at Brechin), and over top that in levels 2-3 is the Lindsay Formation. At the very top is the Collingwood Member with rich black shales that are easy to split. The Isotelus trilobites here are huge. Sadly, you mostly encounter fragments. This piece here would have belonged to a critter at least 14 or more inches long. Massive genal spine, likely from an Isotelus mafritzae. Someone got to this one before I did! That lucky collector hopefully got this one cut out of the rock. It looks like an intact Isotelus roller. Apart from some blast/quarry damage, it is likely complete. Another early part of the day find, a partial Isotelus mafritzae. It is sadly a common feature that the eyes get busted off. I don't want to give the impression that the collecting was as simple as stumbling over thousands of this lovely fossils: you could scan quite literally hundreds of tons of rock and find very little beyond occasional fragments. Apart from some occasional brachiopods or crinoid stems, there isn't a lot of diversity in these rocks, so it is pretty much trilobite or bust! It's also rough going... I was having to scramble over enormous building-sized piles of rock with a bucket and heavy backpack on uneven slabs, so not so easy as it looks! Some of our more seasoned veteran collectors didn't make out so well this time around. One found a few mostly complete Ceraurus, and another collector find a nice plate of full - but somewhat damaged - Pseudogygites, but some of our best collectors made out poorly or were entirely skunked. But at the very least, I think everyone came away with something even if it wasn't a prize and pristine Isotelus. More importantly, it was great to hunt with everyone. This is just part of the head of an Isotelus. It would have been, full, at least 13 inches long! This was an encouraging find as I was gradually becoming a bit more discouraged in not finding anything complete. Another sweet, if incomplete, find. The trilobite Pseudogygites latimarginatus also occurs in this tough limestone, but unlike how it appears in the upper member of the Collingwood shale, they come out with a fine exoskeleton texture and fully inflated rather than flattened. This one I carefully extracted from a very large slab. It has some thorax, which is much better than the zillions of just tail moult pieces one usually encounters. Pseudogygites and Isotelus are effectively closely related species. partial roller missing a lot of parts. I put the biggest fragments I came across into the collecting bucket as a souvenir of the trip. Just... wow. A fragment alone almost a foot long! I pulled this rock out that had a thin line running through it which I suspected to be an Isotelus. When I got home I split it and out came a fragment. A fairly mighty one. As our time was coming to a close, Deb and I made our way to the uppermost level where there are enormous books of black shale belonging to the Collingwood Member. There are quite literally thousands of Pseudogygites latimarginatus and Triarthrus eatoni moulted bits among the brachiopods. Finding a full one of either is not easy, and so you have to split shale in massive volume. Fortunately, it splits easily and finely, and it is like the pages of a book. If I had a trip-maker, it might be this small but full Pseudogygites above, showing both the positive and negative impression.
So, wow. What a trip it has been! Three days spanning over 400 km and three quarries - Arkona, Brechin, and Bowmanville. I was able to collect with old friends, and make new ones. Although I don't think I found anything scientifically significant, I did manage to collect some very nice specimens (including that pair of Greenops on a single plate!). I was able to add two more species of trilobite I did not have (Amphilichas ottawensis and Isotelus mafritzae). I'm hoping this will be an annual tradition from this point on. It sure is exhausting, though! But the thrill of the hunt, the camaraderie of being with other collectors, the sharing of knowledge, and all that lovely fresh air and sun does one good. Reflecting on October, it has been a great month for collecting. I've been to Arkona a few times, to Brechin and Bowmanville, three days at Penn Dixie, and even found a new species of trilobite in my backyard region. And inasmuch as October has been a true surprise, this year has long ago distinguished itself as the absolute very best year for all things fossil. So what's next? Winter is just around the corner, and maybe - just maybe - I might be able to squeeze out one or two more trips before I have to put away the hammers for the season. But with my air eraser, and my air scribe coming, I can at least spend those cold, snowy months preparing all that I have found this year. Day two saw Deb and I make the 3.5 hour drive to the quarry in Brechin with its diverse Ordovician fauna in the Verulam Formation. We had quite the crew with us, and about four are missing from this picture (actually, five, as Deb is the photographer). Deb and I were the late arrivals (11:30 am), while just about everyone else had been there probably since sunrise! I actually didn't meet up with everyone until the day was done; they were done at the base of the quarry hacking things out of the blast piles and the underlying Bobcaygeon Fm, while I was busy on the upper ledges doing some surface collecting. I've never had much luck splitting at this quarry. In about four hours of collecting, I barely made it even a quarter around that one long ledge. I climbed a slightly higher ledge and saw that someone had been there before me hacking some layers out. We use marking tape (or actual markers and piles of stones) to let other people know that these specimens are claimed. It would be considered bad collectors' etiquette to take someone else's claimed finds. We do this when our extraction equipment is parked on the far side of the quarry with an intention to return later. Pictured here is a very long crinoid stem. Another "off limits" beauty: a damaged but still impressive Endoceras proteiforme, the biggest nautiloid species in this formation. A typical hash plate to show a snapshot of the marine floor from 450 million years ago. Although just the impression of a partial pygidium, any piece of this rare trilobite Amphilichas ottawensis is worth picking up. This is a new species for me. Probably the biggest Prasopora I've found at this site. They are fairly common, but this one stood out for its size. The nautiloid fragments here can get quite massive. Assorted goodies here. At the top is a nautiloid fragment, to the left is a trilobite burrow (rusophycus), and on the lower left is a tiny shell hash. Top row: mostly Rhynchotrema capax - quite abundant in the formation. Middle row: some gastros, including Lophospira, Fusispira etc. Bottom row: two pelecypods (from Bowmanville!), two trilobite fragments, and a bryozoan. Another assortment. Of note in this piece would be the very nice gastros here, but also the Ceraurus cephalon at the lower left next to a 2/3 complete Isotelus gigas and another nautiloid fragment. Did someone say Isotelus gigas fragments? Here are a few I picked up. The fork-looking piece in the lower middle is the hypostome (a kind of biting mouthpart that appears on the ventral side below the cephalon). My prize finds for the day: a finger-long gastropod, a small but 2/3 full Isotelus gigas, and two full Flexicalymene senaria rollers. The one on the left is quite inflated and looks like a fat cartoon duck when looking at it from the side.
So began my three day, three quarry adventure. On the first leg of the trip was a visit to my usual haunt, Arkona, but this time it would involve some great visiting friends and fossil comrades (Malcolm, Dave from Philadelphia, and Joe K.). Dave was more keen on plumping up his brachiopod supply, and was eager to get collecting in the south pit. Dave is no slouch on the trilobite front, though... He has gorgeous specimens that I would certainly like to have in my collection. Malcolm made the long drive to my place and arrived around 7:30 am, and off we went to Arkona to meet up with Dave. But before we left, Malcolm showed me a Moroccan trilobite he had prepared for Dave: Definitely big props to Malcolm's prep skills. This one has spines coming out in 3D, including a crazy trident protruding from the glabella. Just wow. This picture was taken halfway through the day. While Dave was off in the south pit, Malcolm and I didn't really budge from our bench in the Widder. Malcolm was heading west, and I was heading east. We moved a heck of a lot of shale. I do not look forward to what will have to happen next once we run out of the left and right areas as that will mean cutting into the cliff, and that will mean chopping out a lot of overburden. I was already having to approach the Greenops-rich layer from the top, cutting out 4-6 feet of shale that only contains bits and brachs. But the search was a success in many ways. I came away with three Greenops, and Malcolm with two. That's pretty stellar results when finding one full specimen is a trip-maker. This one is a bit of a bummer given that some parts have flaked off. Still, not a bad piece that I can gift or trade. I have a habit of picking up nautiloids from the Widder given how nicely they can pyritize. I did find a Tornoceras uniangulare, as can be found in this layer, but it is so pitted and in such bad shape that I'm not going to bother posting a picture of it here. But the real trip-maker for me was a plate with two Greenops. It also had impressions of other full ones. This must have been quite the death assemblage, and it is a little disappointing that only two survived. But here is how I found it: Nervous as I was in attempting to prep what would be a $1,000 plate, I just need to make the attempt. After about an hour using the Dremel to carefully remove some bulk matrix, and a sewing needle to work carefully around the specimen to reveal more of it. And this after another hour using more sewing needle and the Paasche air eraser using baking soda at 25-30 PSI. Not perfect as this pair has a few problems, but not a bad first try on a very tricky piece! I might do some fine touches on it later.
In all, a good first leg of the trip, and great to meet up again with Malcolm, and meet both Dave and Joe for the first time after only knowing them via the Fossil Forum. My fossil forum friend, Jason, had sent me a great assortment of fossils which arrived on the first day of my three-day fossil trip. Have a look: these are mostly from Calvert Cliffs, and includes some great Miocene shells and plenty of teeth, plates, and... on the far right is the Cambrian exception: the tiny trilobite Perenopsis (actually: Itagnostus interstricta).
A short post today before I'm off for three days at three different quarries. So I spent the latter half of the morning at my usual spot just beyond my backyard, cracking rocks in the rip rap pit. There is a wide variety of formations present, all of them in a big jumble. I do know that they largely span the early to mid Devonian. I was not expecting to find much as I've been there so many times that it has become the victim of my picking it over! However, surprises still happen on occasion. A new entry to be included in the trilobite gallery. Initially, I thought this was just another Anchiopsis anchiops, as their tail fragments are among those I find on occasion in these rocks. But it is not quite right. These are images from Rolf Ludvigsen's 1979 book, Fossils of Ontario: The Trilobites. The one on the right is the closer match: Coronura aspectans, which is found in the Dundee Fm. .How I can suspect it is Coronura is based on a few observations: 1. The pygidium of my specimen does not taper in the same way as an Anchiopsis; 2. The number of pleural pairs is very high; 3. The axial lobe is relatively thin; 4. There seems to be small concavity at the pydigium's edge that would either have been a single spike (no) or the two-pronged spike of a Coronura. And so, as tentatively confirmed by my TFF friend, Don, I'm going with Coronura aspectans. Awesome! *****But wait, there's more!***** Actually, the tentative ID is incorrect. It was tentative, just for the record, based on a poorly preserved specimen. Scott, our trilobite expert on TFF, has given the ID as Trypaulites erinus from the Bois Blanc Fm. Not a new genus for me, but definitely a new species. Here is the picture Scott referenced, put next to another image of my specimen. We have a dead ringer! So, a few things to mention here. T. erinus is described in "STRATIGRAPHY AND PALEONTOLOGY OF THE SYNPHORIIDAE (LOWER AND MIDDLE DEVONIAN DALMANITACEAN TRILOBITES)" by Pierre Lesperance (thanks again to Scott for the reference, and from where the image above comes).
Second point being that this specimen is only known by its pygidium; no other parts have been found. I suppose there is a chance that this is not a common find. This year has had a lot of these moments where I seem to find uncommon/rare trilobites for which only fragments are known - or, in some cases, no specimens have been recorded where I found them (but they are described in equivalent units elsewhere). Finding fragments may seem like a bummer, and a lot of fossil collectors would pitch them aside in search of a full specimen, but there are specimens out there so rare that finding a fragment is a significant event. It looks as though the "rip rap hill/pit" behind my home is a veritable trove of uncommon specimens. And to think, several years ago, I just ignored a lot of the rock there or assumed it was just dull Dundee stuff. I've now found five distinct genera at this location, and I can only hope more rock gets exposed for me to split. At the same time, trilobites are not abundant at this location; many have been the trips when I came back skunked without even a trace of trilobite, and I would say it is now about 1 in 5 trips that I find even a single trace. But I need more weathering and exposure. I am pretty much running out of rock to break, and spending my time sifting through tiny shards of my own previous visits is unlikely to make for a lot more winning visits. I simply have too much work at the moment to dig into all those Penn Dixie finds, but I did manage to play with one roller yesterday morning. On the far left, this is how I found it, barely peeking through the shale. I had a feeling it was complete, so I put it in the bucket. The next image is what it looks like after a bit of work with the Dremel and dental picks. On the far right is after using a small flathead lens screwdriver. The purpose here is to eventually free it from the matrix, but trenching around it is a good idea to avoid accidentally causing a crack to run through the specimen. Using sturdy tongue and groove pliers, I was able to clip off the matrix to free the bug. Not a bad looking one, although it is more crushed than enrolled. There's also a tricky bit of "underbite" where the pygidium protrudes farther than the cephalon. On the right is what it looks like after some sewing needles and 20 minutes of air abrasion at 40 PSI using baking soda. It still has some stubborn matrix to remove, but that may have to wait until I can get my hands on some dolomite as blasting media. Still, not a bad job compared to what it initially looked like!
Day Three We had started around 4 pm the previous day in "brach city," an area that is close to the small tributary. This is an ideal spot to find a lot of Spinatrypa spinosa, Mucrospirifer audaculus, Athryris sp., Orbiculoiodea sp., Pseudotrypa sp., Rhipodomella sp., and Mediospirifer... The shale here is very crumbly, so these ones pop right out of the matrix. Trilobite pieces can be abundant here, but very rarely complete (comparable to the high energy coral biostrome of the Hungry Hollow member). The Mucrospirifers can be quite fragile and a challenge to find intact, but we got a bunch. We filled a bucket and planned to spend our final half day before leaving just focusing on this area. It is also filled with crinoid stems, bryozoans, occasional pelecypods, and other marine bits. And thank goodness for easy pickings! My hammering arm was sore and my grip strength felt pretty weak. A bit of a mucky layer, but you can pick out the shells in these pieces, along with the impression of a Greenops cranidium and an Edredgeops cephalon. Not the most exciting picture, but it gives insight into what the layer looks like with all the brachiopods just waiting to pop right out. There are clustered areas in the layer where the bigger shells congregate, and this is one of them. A sweet and uncommon find in this layer: a full Eldredgeops rana that is very tough to find in these crumbly layers. Pictured on the right is what it looks like after some delicate work with a dental pick. We filled buckets with brachs. This is just one of them. We managed to collect about a thousand intact brachs. It will take me some time to clean and sort them all. A small pile of spirifers (Mucrospirifer and Mediospirifer). For scale, most of these are almost two inches wide. A small pile of Spinatrypa spinosa. Some can be quite large (about the size of a silver dollar) and came out either thin or plump, single or dual valved. A small pile of Pseudotrypa sp. They come out either somewhat flattened or very plump, a bit bigger than cherry tomatoes. Again, hardly representative of all the examples collected of each species, but cleaning and sorting of 1000 brachs will take time! We have here some Athyris sp., Rhipodomella sp., and another species I have to double check.
My next post will be the "aftermath" portion where I actually go through the large number of buckets filled with fossils, and get those to the prep table! Stay tuned... Day Two The weakening vestiges of Hurricane Nate had made its way northward and gave Western NY a bit of a soaking. The weather forecast up to this point had been inconsistent to say the least, so it was really a gamble on what this day would bring. So we did a little bit of shopping in the morning, and by 11 am or so the rain finally stopped. So it was back to the site. However, so much rain had fallen that we were met with a fairly flooded area. That bench I carved out the day before? A little lake. Those slabs I cut out the day before were on top of piles of overburden, so we were able to spend some time breaking those down and finding some good rollers and the occasional prone. Although the torrential rains had stopped, the drizzle was constant. Rocks got covered in mud, my gloves became slick and muddy along with the tools, so it made work very challenging. I spent about and hour bailing the muddy water out of the bench with a bucket, and we spent another hour or so scraping and shovelling off goopy, sticky overburden. I was then able to hack out a near shopping cart sized slab that took a lot out of me. With some artful use of a wedge and pry bar, I was able to lift it just enough to get my fingers in and do a mighty pull by securing one boot on a ledge and the other stabilizing it so it wouldn't fall on top of me. It took about five or six tries, but I was able to get it on its side and start carving. The stuff was very dense and not cooperating as bedding planes just weren't a thing for this rock. Still, I managed to turn a boulder into shards, probably bagging little more than ten or so trilos. Not a great return on investment! By about 4 or so, there really was no point continuing with this bench. Water was filling back in and I couldn't determine where the bottom of the slabs were except by touch. Also, the water had seeped into the cracks creating additional suction. I was just too pooped with the big slab anyway, so off we went to the brach area. The not so great lakes. Wet, muddy, drizzly, and almost impossible to work. This layer was "sticky" and dense, so some of the carapace got stuck to the impression side. That's a real bummer as this one is a complete prone. On the left, a trilobite peeking out at the contact edge of a slab. It came out full and fine. On the right, a headless one, but fairly large at about an inch wide.
Deb and I came back from three half-days at the Penn Dixie site with an ok mix of finds despite some weather and site challenges. This is usually an ideal time for us to get out and collect as Monday was our Thanksgiving, and my university has implemented a new Fall Reading Break. However, not everything went according to plan! Day 1 We arrived around 1 pm and left before sunset. The site itself is vastly different from when we were on the big TFF dig back in April. After the Digging with the Experts, a lot of overburden seemed to have been dumped on areas we had been working. About 5 or more feet of the stuff, actually. Usually one will find a spot where a bench has been started, and that becomes the starting point for expansion. Not so much this time around as it more meant starting a bench from scratch at the right spot where the trilobite layer is. I found an entry point about a foot and half wide and we got to work moving about a foot or more of overburden. I then starting carving out slabs and placing them on the piles of debris we were scooping up (I'm glad I did as Day 2 will make clear). There was a slightly higher proportion of Greenops bits at this spot as I suspected from the general area we had covered last year. Pictured here are some slabs. The first one with my rock hammer dangling was resting on a very smooth inclined layer that ran about 4-5 feet wide and about 3 feet deep. The bottom half of that slab is about a foot and the top tapered part is only about a few inches. The one I pulled out the next day was a real monster at about 2.5x larger and about 400 lbs, and it took a heck of a lot of energy and several tries to wrestle it into an upright position. My back was pretty sore after that! The other slab pictured has some promise as there are some trilobite parts showing. Ultimately, I was in search of a trilobite party, and the stuff at the base of the inclined layer seemed to hold a bit of promise for a multi-plate. Some of the slabs I was talking about. The second one has some trilobite promise. These pieces above have trilobites. The one on the right is a little trilobite party! Who is that peeking out? Judging by the broad and uniquely styled genal spine, it is none other than the very rare Bellacartwrightia whiteleyi in an awkward diagonal position through the bedding planes. This will take some preparation finesse! This is how I left the bench at the end of Day 1. Looks promising, doesn't it?
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Kane Faucher
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February 2024
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