I can hardly believe it is mid-June already, which means I'm at the halfway mark between the end of the winter semester and the beginning of the fall semester. In my post-Bowmanville week, I've dabbled with some prep, and even some illustrations -- although the latter have been all misfires as I'm having challenges drawing a Walliserops.
Firing up the compressor in the lab, I've managed to eat through a few boxes of baking soda. My first engagement was to finish up that placoderm (see the post on that here). Next up was to get back to the trilobite preps. First up was that lovely prone Flexicalymene croneisi I found at Bowmanville.
Here is a before and after. Both eyes and the distinctly granulated preglabellar lip are intact and pristine. Only light scribing in some spots around it, and some dolomite as well. On the bug itself, it was pure baking soda, with occasional baking soda - dolomite mix on tougher spots (5::1 ratio). Specimen measures 3.3 cm tip to tip, and prone examples are considered rare while enrolled ones are relatively abundant. This species only appears in the Hillier Member of the Lindsay/Cobourg Formation. Currently, it sits atop a softball sized block of very hard encrinal stone that cannot be scored and cut using the ME-9100, and so I've purchased an angle grinder for that task so it can sit safely in the display case.
Another before and after, this time of a Flexicalymene senaria traded to me by a good friend. This one had a few issues with post-mortem compaction damage and a very hard brach and bryozoan attachment on the lower right pygidium that could not be removed for fear of tearing off the shell, so I left that largely in place. The crinoid stem runs underneath this one, giving it the appearance of some kind of fuel line. Despite its problems, it's cabinet worthy to me.
There are still more preps to come, but also at least two fossil trips in the coming week. Once the angle grinder arrives, I'll be playing with that to cut down a few bulky items -- it will be far less tedious than having to do that with the scribe!
Next up, an illustration of a friend's Isotelus gigas that we all know as "Kermit."
This is my second blog post today. I took the time to finally complete this placoderm I found in the Widder Formation back in April. I started it not long before I left for Bowmanville, and tidied it all up today. This is likely Protitanichthys sp. (cf. rockportensis), but more research needs to be done on these arthrodires.
This is an in situ photo of the arthrodire -- a completely discombobulated mess. To make matters more fun, it was situated in the iron-hard brachiopod layer, so the only choice for extraction was to use brute force and hopefully be able to collect all the pieces for reconstruction later. Apart from some of the bigger pieces, it is not entirely clear how this critter is oriented.
I had put it aside to deal with trilobite prep, but I knew at some point I'd have to do something with this so it wasn't just sitting and taking up space in the living room. I started assembling some of the bigger pieces; the smaller pieces were going to be a lot of trial and error -- a bit like doing a jigsaw puzzle without the completed image on the box. There is a lot of matrix to remove as can be seen above. These are otherwise thick pieces of bone that made up the head and dorsal shield of this Devonian fish.
At this point, after about ten hours, I've taken to abrading all the little pieces as well (not all pictured here). The matrix was very easy to remove in parts, melting away under baking soda... But some of the matrix was sticky and as hard as iron. Scribing was not an option when the matrix is this close to the bone as there may be pustules hiding underneath that could easily be knocked off with a far too aggressive approach. Slow and steady is required.
Jump ahead another ten hours and it is done. This is pretty much solid bone. It is also of substantial size for the Widder at about 20 cm from the tip to tip, and this is just the posterior median dorsal plate of the trunk shield (the complete placoderm would have been over three feet long). I've glued it down to a piece of black construction paper and will likely clean up around the edges before pasting it down to a harder backing. There are three small pieces orphaned that I can't find a place for, and there is sadly some missing pieces that must have been lost at the site -- but none too shabby under the circumstances of its forced extraction by necessity. I'm somewhat proud of this one.
Recently returned from the biannual quarry trip in Bowmanville, Ontario. Overall, I didn’t do too badly, but I also didn’t come away with the great spoils one dreams of finding either. Traditionally, the trips take place in May and October, but a change in management shifted the spring visit schedule, and so early June was our date. The new quarry manager is fantastic and shows a keen interest in what we get up to. Just as long as everyone abides by safety protocols, we will continue to benefit from this incredible arrangement.
Here is our wrecking crew:
Someone in our crew made one of the most significant finds at this quarry. Sadly, that someone wasn’t me! But do have a look at this phenomenal mass mortality slab of 20+ Ceraurus — zoom in and count them. This is going to look amazing once it is fully prepared.
Another of our crew found this massive, eye-watering nautiloid:
My own finds were fairly modest. As the quarry was operating, we had some restrictions on where we could go, and so much of the day was spent on level 4. There are six levels in this vast quarry. The rock in the bottom five is Cobourg/Lindsay and Verulam Formations, and pretty hard. Isotelus bits dominate, while full specimens are a bit harder to find. There are over 20 species of trilobite in the Hillier Member, but most of them are rare. The more common trilobites are Isotelus “mafritzae”, Flexicalymene croneisi, Ceraurus sp.
My trip-maker was this Flexicalymene croneisi. As they more commonly come out as rollers, finding a prone example is certainly good luck. This was in a block the size of a small car. I chiseled out the layer, but the rock was still a good 150 pounds and I am grateful to one of our collectors for taking the time to saw it down for me.
Isotelus pieces could sometimes be quite large. Here is a busted pygidium with my one inch chisel end to indicate scale. A complete specimen of one of these would be a museum piece, for sure.
Other partials of note. I keep these for trades:
Isotelus juveniles. The one may or may not be complete in the rock, and the other is nicely inflated although missing some shell from blast or weathering damage. The latter was found just sitting in a bit of mud.
Plenty of gastropod steinkerns to be found, too:
Didn't come away with any complete Ceraurus, but I held on to these partials:
Not quite sure about this one yet. It might be a Bumastus, but it will need to get some treatment in my lab to be sure.
Even if I had gone away without finding anything, I still would not have left empty-handed. A trade with a good collecting friend of mine means I’ll have some fun preps in my future. First up is a pair of Flexicalymene senaria prones from Brechin, Ontario:
A buried Ceraurus from Brechin. The right pygidial spine may or may not be there:
A complete and enrolled Calyptaulax, also from Brechin.
Two prone Gravicalymene from the Montreal area. A new species for me.
No prep required on this one -- positive and negative impression of Aulacopleura konincki from the Czech Republic.
Overall, not my greatest outing, but also not a skunked one either. It is a lot about luck here, and dividing the time trying to cover a lot of ground searching the blast piles and splitting. Scrambling over those piles is not easy as you want to ensure good footing — not always easy on very irregular surfaces, some of which can be a bit treacherous. It’s not the easiest material to work with, but rarely is anything good easy — it is likely the first rule of advanced fossil collecting and preparation!
I'm chomping at the bit to get to preparation of some of these finds, but it will have to wait until I'm done my current task on a large placoderm bone/trunk shield.
I haven't got out to collect anywhere nearly enough this season, and we're already cruising into summer. But I have been working steadily at the drawing table and the prep bench. I'm just about done all the more recent fossils in the preparation queue, with mostly tedious stuff left.
Pictured above were some very awkward, crushed Penn Dixie Eldredgeops rana that I took on as a prep challenge. There wasn't much showing initially, but I knew they were complete despite their contorted orientation. This was a very delicate prep as crushed bugs like these are riddled with cracks, and it wouldn't take too much abrasion or even handling to pop off shell. They are very thin, but I'm proud of the effort I took to do these up properly.
This is a closeup of a very wee bug (~1.7 cm). There's still some matrix in the segments to remove, but it is effectively complete.
Given the number of rollers I have on hand, I can take a few more adventurous risks in preparation. I've done quite a few pedestaled rollers already, so in this case I wanted to cut as deeply as I could into the ventral side. In this one, I've exposed the cephalic doublure, and a portion of the hypostome (the rest is tucked under the impacted pygidium). Soon I hope to do a full dorsal-ventral prep.
This is another wee bug (~1.7 cm) with problems that make it more a B-grader, and so ripe for a prep experiment. What is not shown in this top-down image is my attempt to pedestal this one -- a trickier proposition with a smaller prone.
The two images above show the tiny bug's suspended/perched state. I could have been even more daring, but for a first try at cutting under a prone, I'm happy with it.
I was able to spend the day mucking around in the Hungry Hollow Member. Lots of the usual stuff that I won't show here like gastropods (a very large Spinplatyceras), and acres of coral that just gets in the way of this turbid bed. My goal was to find complete examples of the trilobites Pseudodechenella and Crassiproetus. Fragments abound, but in this puree of a depositional environment full specimens are quite prized and rare. Obviously I did not succeed in finding a full one, but the cranidium of a Crassiproetus above is quite massive (~2 cm along the sagittal), which would have made the full one 6-9 cm in length. I cleaned this one up using baking soda abrasion.
And relatively fresh from the sketching table, two relatively common but cherished Ordovician species. I am trying out a few new tricks on achieving some degree of photo-realism with pencils, and I think it is paying off.
My next post will likely be after the weekend biannual trip to Bowmanville as I hunt one of the few remaining locations for decent Ordovician material. Until then...
Although it is fossil season, I've not managed to get out much lately beyond some rummaging in the Hungry Hollow Member. Instead, I've been busy with prep and drawing. I'm not quite ready to show the prep just as yet, but I've got some new trilo-doodles. Next trip will likely be Bowmanville in June.
Now that my replacement stylus has arrived, it's back to the lab. I've got a bit of a backlog of pieces to prep, so I could have worse problems! I prepare my fair share of these bugs, but this one will present some opportunities to try out some new preparation approaches.
This is how I found it in its field fresh state at Penn Dixie. I bucketed it on account of seeing the full roller.
Another WIP is photobombing this one at the top, but after some exploratory scribing, I encountered two more rollers. Sadly, my scribe blasted off a piece of the middle one, but I can do some restoration with Milliput once I'm done. My goal here is not to be as trilobitocentric, but to prep the brachiopod at the top, and the rugose coral below to make it an association piece emblematic of PD fauna.
Who needs acres of bulk matrix? My ME-9100 sails through the stuff. The leftmost bug is pretty much fine as it stands without more bulk matrix removal, so it just needs a good blasting. I'll work to expose the middle bug's cephalon, but have to be careful not to overexpose its pygidium and thorax given its close proximity to the brach and the other bug. Still, I can do some very precise work with the Aro to create a kind of "channel" between them. The rightmost bug has its cephalon matrix-down, so I'll prep this one with its back showing.
Just to give a sense of the levels I'm working, this perspective shows it is not just like a flat slab. I've been carefully exposing more of the bugs as well as the coral and brach. Once that is done, matrix prep, blasting, and final touches. I'll update this as I go. Stay tuned...
Having just finished teaching a week-long course, and with no work currently penciled in the schedule until late June (although that could change), I can dedicate some serious time to fossils. This means collecting, prepping, and drawing.
I'll be prospecting some new possible sites. Once a site has been picked over, tapped out, or shuttered, it's time to do the work of exploration and field survey. That means extending the search and testing the layers (or the heavy work of exposing them). Once that is done, an assessment is made as to the site's productive life-span: is it something that will last several seasons, or something an individual can clear out in a few trips?
Apart from that, I got word that we are a go for a June engagement at one of the last quarries that still lets collectors in, so I'll have that to look forward to.
It's also time to get some prep done. First up is this 80 mm asaphid, but there are a bundle of Penn Dixie bugs to work on as well.
This is where it stands after about six hours. Apart from some sticky calcite on the right cheek, this has been a delight to work on, but having the ME-9100 makes matrix removal much easier. In fact, since I'm waiting for a replacement stylus for my Aro scribe, I did all of this with the ME-9100, and it is great that I can dial down the BPM when I get close to the shell. There's still some work to do, such as removing matrix between a few segments and the base matrix smoothing, but I'm awaiting some scalpels in the mail to do the inter-segment and touch-up work. As an expert Russian preparator told me, never use abrasion: it burns and lightens the skin no matter what medium or PSI; it must be done by hand. That was my error on the last Asaphus lepidurus I prepped.
I was far too busy and tired this week to put pencil to paper, but I have two WIPs, a few sketched concepts, and Deb bought me some black paper so that I can try out drawing white pencil on black background. At this point, I'm pretty much looking at a 20 hour backlog of bugs to doodle.
Update: Managed to get three since Friday.
The last bit is some tidying up of the trilobite catalogue. I recently acquired this piece, which is a Cambrian Hamatolenus sp. from Morocco.
This post is more a stub, and I'll update it when I've rolled up my sleeves for some of the stuff I mentioned above.
In the last month I made an investment in a new camera. Previously, all my pictures have been using my iPad. The iPad is not an awful photo-taking device, but it does have its limitations when taking macros, and any of the add-on apps like Camera+ only make a small difference in quality. There are very small trilobites or details thereof that could really use a more effective camera.
And so I am now the proud owner of an Olympus TG-5. I won't list all the neat features as that can easily be Googled, but it also very conveniently doubles as a great and rugged field camera. The other feature, relevant to fossils, is its micro/macro functionality. The micro has an in-built photo-stacking feature to resolve issues of depth of field (the closer one zooms on an object, the more radial blur occurs -- something stacking fixes). When I take a very close-up image using the stacking, the camera takes multiple shots at slightly different angles and depths, and flattens the crispest aspects into one image. So I took it out for a bit of a trial run on some trilobites:
Nice, crisp closeups. Just to give a sense of scale, the agnostids in the second picture are only a few millimetres long. Next are two images of the same trilobite (Eldredgeops rana) at different zoom levels:
Overall, much better than using the iPad. The camera was not cheap, but I'm quite pleased that it will be able to serve a useful function for more than just once a year when I'm in Jamaica.
Recently returned from a three-day dig in New York. Despite all the lovely weather leading up to the trip, an almost wintry weather system was working its way through this part of the world with a lot of cold and precipitation. Not exactly pleasant collecting conditions!
Day 1: Penn Dixie
The excavator had been busy the days leading up to our visit. 160 fresh new piles of Windom shale were dug up and off limits until the annual Dig with the Experts event in May. The excavator did dig up one promising area. One of my field comrades had already visited the day before to start a bench and was finding some good material.
Friday was brutal. We only managed to stay out for three hours given the pouring rain, sleet, and the lake wind. In fact, it was so cold and wet that I didn't really take any site or collector pics.
Despite digging for only three hours, we still managed to find examples of just about every trilobite species reported at the site, missing only Pseudochenella. The two above are Bellacartwrightia sp., Eldredgeops rana, and the bottom two are Greenops barberi and Dipleura dekayi. The Dipleura is exceedingly rare at Penn Dixie, and was found in the Bayview bed.
Day 2: Deep Springs Road
Now an annual tradition, Fossil Forum members congregate at a spot in central New York, a shale outcrop on Deep Springs Road. It was snowing for a bit. Deb sat this one out, but went to Penn Dixie later in the day to find some trilobites.
As I had already hoovered up most of the usual fauna from this site last year with representatives of most of the brachs and bivalves, my sole goal was to find a complete Dipleura dekayi. Sadly, my efforts were for naught after six hours of slabbing and splitting. Most other stuff I found I gave away to other collectors there.
I did find these two phyllocarid carapaces (Rhinocaris columbina) that I gifted to my good friend Tim who had also found an amazing phyllocarid telson.
I didn't do so well on the trilobite front. It was mostly partials for me.
One of the other traditions of this meet-up is that we exchange fossil gifts. Pictured above on the left is a chunk of dinosaur jaw from Tony that could be Triceratops or Edmontosaurus. Top right are two Elrathia kingii from James who just came back from Utah, as well as some belemnites and a gastropod from Jeffrey's giveaway box. For my part I offloaded two bins of fossils to Tony for his museum. At the bottom is a fantastic gift from Tim: a Dipleura dekayi hypostome (very uncommon!) and Piochaspis sellata from the Pioche shales of Nevada.
To my good friend Tim who is a fish fossil fan, my only non-trilobite drawing. Knightia eocaena.
Day 3: Penn Dixie Again
Initially, Jay and I had plans to collect a few hours in Dunkirk where it is rumoured that Dunkleosteus pieces could be found, and a generous offer to go through some Linton coal in search of Pennsylvanian aged fish and amphibians. Things didn't work out that way, and I was kind of itching to find more trilobites at the first spot we were working on the Friday. This time, the dig was not curtailed by weather: it finally got warm and sunny. I spent 12 hours hammering and slabbing.
This is the only site pic I took, and this is a "before" image at 7 am. The chunks of rock in the foreground need to be broken down, and the area around my bucket and pry bar is the bench. By 7 pm, all of that area was cleared out.
As the day progressed, the trilobites were thinning out. I made my last significant find around 3 pm, after which it was mostly coral/brach assemblages in very tough, trashy matrix that would shatter rather than split.
Not much to write home about. This is actually a small haul compared to my usual 50-100 bugs per trip, but the pulse was pinching out and the site's excavated areas may not be ideal for trilobites this year. Still, some interesting pieces to prep.
And speaking of which, I've already thrown one into the lab to give my new tools something gainful to do. The initial field state was only showing the thorax. I used the ME-9100 to remove a lot of the excess rock, the Aro for detailing around the bug, the Paasche for abrasion, and decided to pedestal this. Matrix work was mostly filing and sanding. This kind of matrix preparation is not everyone's cup of tea, but these are common bugs and I wanted to play around with some presentation experiments.
And that's it. Not sure where/when the next trip will be given the sad shrinking of viable or accessible sites in Ontario. But I'll find a way...
Tomorrow we'll be off and away for the first site, Penn Dixie, and then Saturday for a Fossil Forum group dig at Deep Springs Road. The weather promises to be wet, cold, and miserable, but the alternative is to pass up a rare opportunity to get out and collect. There's no sense in having all these new tools and no new material to work on.
In the last few days, I've been able to try out the new tools. The first order of business was to clear up my prep area as it was a bit of a disaster. I was going to get all four of my tools hooked up into the new manifold block, but at the moment I just can't seem to fix a few air leaks... And these fingers are not nimble enough to use the teflon tape very well, and the tube sealant just creates a goopy mess. So for now I'll be swapping out tools using the quick-connect until I can get my hands on something better for the leak issue.
So this is the little corner where the prep magic happens, what I cheekily call my "lab":
The new 20 gallon compressor is great. The bigger tank means it isn't running constantly, which is important as I'll be running the new tools at 110 PSI.
The ME-9100 was the first tool I tried out of the box. Taking a junky Penn Dixie trilobite in shale, the scribe sailed through the matrix easily. I tried it again on some tougher limestone from Bowmanville, and the chips flew. This is a serious tool with some serious power.
The Paleo Aro was next for its trial run. Again, using the same junky bug, it easily (perhaps too easily) chipped off surrounding matrix to reveal the whole bug in five minutes. That same result would have taken me over 30-45 minutes with my old Aro clone. I will have to adjust to the power of this tool and its longer stylus to avoid making mistakes, as I haven't yet mastered the right way to hold this particular tool for ensuring maximum control -- a necessity when doing detailed work around a fossil. After a combined 20 minutes of usage, however, I encountered a problem: it stalled and would not re-engage at all beyond a one or two second "toot." I tapped the housing, oiled the parts, but nothing was quite working, so I got in touch with my master prep friend Kris from Texas to see if he could diagnose the problem. He suggested removing the spring around the stylus base and working it with my fingers, and then to give a bit of oil to the base plate where the second small O-ring sits. And now it works!
Next up to complete this picture will be to either get a new goose-necked lamp, or find a cheap source of circular fluorescent bulbs as the light in the box from the scope's ring light is just not bright enough when working under magnification.
But for now, it's back to packing for the three day trip.