Snow-free until January 10, and then it clobbered us. More time spent indoors and thinking that it will take a while for this snow accumulation to melt and get the collecting season back into gear. So that leaves prep and postal formation.
This is a return engagement with a bug I started a few months ago. It is a giant for the location (Penn Dixie) that measures over 45 mm from genal to folded over genal. What is not shown in this image is the folded over/under side that took a ridiculous number of hours. I also took the time to level and smooth the matrix -- something I am learning to get better at, and which also takes a lot of time and patience.
A very lovely full prone Scabriscutellum furciferum from Morocco.
The seller was also kind to add an unexpected brachiopod surprise to perk the package.
My 100th trilobite species! Asaphellus fezouataensis from a really nice seller who also threw in a little enrolled phacopid.
Still trying to relearn my old drawing skills that have been neglected for nearly 20 years, a pencil rendering of an Isotelus.
A Greenops widderensis...
And an Eldredgeops rana with all the crush/distortion flaws.
So, for now, that's about it. I'm somewhat running out of trilobites to prep, and only expecting one or two bugs in the mail. I really hope winter won't be too long!
A belated birthday gift, but only by a day. Had the rock cut and away I went to prepare one of Deb's most prized finds.
From the field to the final product.
Over the weekend, I was trying to prepare an Eldredgeops rana roller so that it would be nicely presented in pedestal fashion (just to get some practice with that approach). The roller itself was flawless with no cracks from crush damage, and fully inflated. It was going very well until it popped off the last remaining bit of rock that had been holding it in place, and... rolled away. Cleaning out my entire prep area did not result in me finding it, so it has likely been absconded by the same little demons who steal socks from the dryer. Six hours of work gone.
So a few days later I decided to prep my way through that disappointment in completing a trilobite I had prepared before, but not to the full extent. This is another Eldredgeops rana from the Penn Dixie site, and measures on the upper end of the size they appear at this site.
Before and after. I had prepared this halfway months ago, but it still needed more work. When I initially found it, the rock had split right through it, resulting in the loss of some segments. I glued it together in the field. In this round of prep, I applied acetone to get rid of some excess glue, performed some restoration of the missing parts, scribed and abraded a bit more, and this is the result. It may not be perfect, but it is a lot better than how I found it! This one measures 47 mm (sag.).
My next task is to complete prep on one of Deb's finds -- another prone E. rana.
The snow has finally buried us after an unseasonably warmer and snow-free stretch. So that means more time spent in prep, and some hunting relegated to the postal formation. This short post is a quick update on newer additions to the trilobite horde.
New acquisition, the blind phacopid Ductina vietnamica. This genus was quite widespread, appearing in different faunal provinces. These regularly come up for sale, but most of them are preserved quite poorly. This one is a much better example of the species.
A semi-enrolled Paralejurus spatuliformis from Morocco. This one differs from other members of the genus on account of having a, well, spatulate kind of pygidium. This one has no colour enhancements, so appears "in the buff" without having been buffed with shoe polish or some other additive to make them uniformly black. The closeup is of the holochroal eye with its tightly packed lenses that appear, from a distance, to be entirely smooth.
While going through some boxes of old finds and turfing junk, I split a small and thin piece of Verulam Formation (Brechin, Ontario) to encounter this cephalon fragment of the rare lichid, Amphilichas ottawaensis. I haven't heard of anyone in my collecting circle who has spent a lot of time in Brechin find more than fragments. I had found a ventral pygidium fragment a few years ago, but nothing else... And now that the site has been shuttered to collectors, there's not much hope in the immediate future of finding more. The picture below is of a complete Amphilichas halli -- not the same species, but it gives a sense of the body plan and where my fragment fits:
And that is likely all that is fit to digitally print this week. The fragment was the big surprise find while the snows are blowing and the temperatures nosedive.
Before my teaching duties resume tomorrow, I was able to squeeze a few more preps in the last couple of days. Nothing significant, but certainly learning moments for me as I better refine my nascent skills.
Already, I can count a few preparation bouts that turned out fairly well: an Illaenus sinuatus, Asaphus lepidurus, Flexicalymene croneisi, and the Flexicalymene senaria / Fusispira nobilis association. So far, so good, and it seems the normal state of things is to be covered in a fine coating of dolomite!
I probed other finds as well to see if there were other things there, and even popped out a headless Thaleops sp. from Bowmanville. Working with sometimes less than ideal equipment can be its own challenge, but I manage. There are still inefficiencies in my preparation "style" whereby it will take me twice or three times as long to complete a specimen than it would a more seasoned professional preparator with a wider array of tools.
So my task queue has been shortening, but by no means at the point where the lab will be going idle for the rest of winter. My next task was to "fill in a gap" in my "prepertoire": restoration. My first attempt was a mixed result on an Isotelus "mafritzae" back in November that has since been finished but I have been remiss in posting said result. This second attempt would be making use of Milliput again, but on a smaller and more expendable trilobite, the commonly found Eldredgeops rana from Penn Dixie. I've got loads of these in just about every orientation.
This bug was never going to make the cover of Trilobite Vogue. It is twisted with tons of crush damage to the glabella and the right side. For added "character," it is also missing a lot of shell. For preparators, this would be the kind of example one would find in a box of rejects to be harvested for parts.
At this point, a bit of scribing around and blasting followed by applying a good glob of Milliput. Some carving and let to cure for a day.
And the last two stages of the process. If you're wondering, the genal area of the cephalon is largely tucked underneath at an angle (super fun to prep - not!). As far as a clean restoration attempt, it is a pretty obvious attempt (but in certain lighting conditions it is a bit tougher to tell). In my weak defense, I don't have tiny tools or tiny fingers to do this kind of detail work. What this needs is a a pin-sized sander to grind and smooth down the transition between the restored area and the original shell. The pygidium itself is a real mess. But, hey, this was already consigned to the chuck-it bucket anyway, so may as well take the opportunity to practice on a piece that I could royally botch.
An incomplete Leviceraurus mammilloides that Deb found in October in Bowmanville. I may have screwed up in an earlier scribing attempt, not figuring that the tail spines would be sitting on top of the bug's plane, so all but the stubs vanished. It was already missing the left genal and part of the right genal, as well as the right eye that I could not save from the impression side, sadly. But it looks a lot crisper now that I've taken the matrix down on all sides and cleared up some of the inter-pleural gunk on this "zipper bug."
While I had the compressor running, why not do a quick blast of this long-tipped Mucrospirifer thedforensis? They clean up fairly easily, but are usually just a waste of dolomite and time.
And these are teed up for their time at the bench: four enrolled Greenops widderensis (one almost completely pyritized) that will be no picnic to prep. The goal with these will be to expose the other side and have them appear as if "draped" over the rock. These are incredibly delicate and flaky, so having at least four on hand to get it right is a good thing as I anticipate at least a few catastrophes with these ones!
It's been at least a day since the last blog post! On this New Year's Day I decided to get into the lab for one last go at preparation of fossils before I have to hunker down and do preparation of courses for this semester (I rarely need air tools for the latter, heh).
I found this association piece back in 2017. Initially when I found it, just surface collecting the upper floors of the quarry in Brechin, I put it in my bucket thinking it was just a gastropod steinkern. A few weeks or so later, looking over my finds, I noticed this traveler after removing some dirt.
At the time, my only prep tools were a pin vise, a Dremel, and a lot of patience. A trilobite this small would require air tools as the matrix is too hard for a pin, and a Dremel would vibrate this to pieces. So it was left consigned to the "to-prep" pile and forgotten. After having some good rounds of prep in the last week, and a little boost in the confidence of my prep skills, today was the day I'd tackle this wee bug.
The trilobite is Flexicalymene senaria, which is one of the most common trilobites in the Verulam Formation (Ordovician). Hash plates are filled with their moulted cranidia and pygidia, and they are also frequently found enrolled and matrix-free. Full prone ones are a little less common, but in no way rare. What makes this one special, though, is its association with a steinkern of the gastropod Fusispira nobilis.
After four hours of very careful abrasion work, this one is done. It may seem counterintuitive, but smaller pieces do not necessarily equal faster or easier prep work. Much more care and attention is required, and the margin for error is much smaller than when working with larger pieces in similar matrix and preservation conditions.
And so here it is in all its close-up glory. Nice, prone, and robust with just a few minor problems. Prep for 2019 is off to a great start.
There are collecting locations that I'm not likely to get to in the near future, and as much as I'd love to fancy myself wealthy enough to just buy up every great Russian Ordovician bug, sometimes one has to settle for the discards.
Russian preparators who eke out a living collecting and preparing trilobites are not too different than the preparators who do the same thing here: there are those (far too many) finds that are simply not worth the time and effort for whatever reason. It could be a common bug that has too much compaction damage, bad mineralization stains, too many missing parts, or anything else that might result in producing a trilobite that is far less than A-grade for sale. Buyers generally expect perfection, after all, or something close to it. So into the chuck-it bucket it goes. I have my own "graveyard" of partials, botched prep attempts, and stuff far too common yet complicated to be worth preparing unless I had nothing else in the queue.
So this is the chuck-pile bug in question. Not quite complete junk, but pretty close. It was likely found busted and glued together in the field, which is a fairly common scenario when collecting from these layers. For every nice, full (sometimes floor polish enhanced) Asaphus sp. one sees for sale, there were likely hundreds of busted up partials (some of which get recycled as grafting material). This trilobite has a lot of problems beyond the fractures tentatively held together with glue: crush damage, missing shell bits, and serious mineralization discolouration that makes it appear mottled and less than pristine sale quality. But I need the practice!
I've never prepared an illaenid before, and there are always a few "firsts" I encounter while preparing given that I haven't been doing it for that long. Each prep is a learning experience, and making serious mistakes is part of it... But so is recognizing that each prep is different, even when dealing with the same species and matrix. You try different approaches and techniques, sometimes using a wide range of tools suited just for that particular job.
So, let's have at it.
The first step was to do the scribe work, but not before consulting numerous images of this species from different angles to give me a reasonable idea of what to expect while my scribe flies blind. My scribe sailed through this matrix! By contrast, the previous prep of an Asaphus lepidurus was a dismal failure as the matrix was a dense, calcitic mess that even 75 PSI dolomite wouldn't touch unless I wanted to eat through several canisters of the stuff.
The unique aspect about this genus is that the bulbous cephalon seems to go on forever. This was where I stopped the night before, and there was still a lot more matrix to remove. When they preserve in this kind of almost semi-prone state, it is customary to just blitz off the the anterior side of the matrix, which gives this burrowing bug the appearance of "hanging over" the side. This is all scribe work: I just needed to "kiss" it with the tip and the vibration would knock off the matrix without me risking hitting the shell with the scribe tip.
And this was where I had to call it a night... Not just because I didn't want to run the air compressor beyond 10 pm and be a loud nuisance, but on account of the other result of such a soft and yielding matrix is that fractures emerge that run deep and threaten to wreck the trilobite. Pictured here is my stabilizing some vibration-made cracks by wicking some cyanoacrylate. A good ending point for the day to let it cure and get back at it in the morning.
As soon as my missus went to work, I was firing up the compressor for round two. At this point, the scribing work is pretty much done as far as I'm willing to risk it; what remains are some delicate areas that need to be air abraded. I do alternate between scribing and some air dent to test certain spots, but I'm a task-switcher by nature. The tricky spots are going to be the eyes and the genal spines.
It isn't a true prep session unless you experience a minor catastrophe (at least that is the norm for my inexperienced self!). The very thin-shelled underside of the cephalon didn't quite dig my air abrasion action, and so some shell bits went flying. I retrieved a few pieces, which is not easy to do in a dust layer in the blast chamber (or in the shop vac bag). And I don't exactly have those tiny fingers adept at threading needles. I reattached a few of the pieces I found, but some of them were lost forever. It could have been much worse, and I managed to fill in the much bigger "bald spot" with the pieces I could glue back on. This is a discarded bug anyway, and not a presentation to the Queen.
Air abrasion work reveals the eyes and frees out the gunk between the pleurae and the genals. I've moistened it with some oil to better detect other areas I might have missed.
Yes, I am such a prep noob. I will, however, take immense pride in how I managed to free up that genal spine (which had a crack in it, no less) to be my first "flying genal spine." For those who do not prep, this may seem very easy, but it is fraught with a lot of nervousness and care to ensure not blasting the spine off as a sacrifice to the hungry shop vac!
And this is where we are. I also sanded down the matrix (decided to leave a bit for aesthetic reasons). There is some cruddy glue stuff on the left pygidium that needs an acetone bath (abrasion is too risky at that section), but otherwise not bad at all for preparing what had been consigned to being a junk bug. I learned a lot, and ended up cussing a lot less while doing this one. To me this is a prep triumph.
Made a trip to the post office to pick up a backlog of packages that couldn't be delivered at the door, and it was a lovely little bonanza of bugs.
Although a bit beat-up and sticky, this will be added to my winter preparation queue. This Ordovician corynexochid is Illaenus sinuatus, a new species for the collection. The cephalons on these kinds of burrowing bugs tend to be fairly robust, so there is considerable matrix to be removed. I'll post the complete results once I get this in the lab.
Another Ordovician trilobite, the phacopid Pliomera fischeri, from Kinnekulle, Sweden. Trilobites from the Swedish part of Baltoscandia do not tend to preserve as well, and can come out fairly weathered.
From Haellekis, Sweden, an enrolled Ordovician phacopid, Nileus armadillo.
Although I already have two other examples of this species, a small and enrolled Asaphus kowalewskii will nicely complement the Russian asaphid display.
Top prize for this bug bonanza would go to this lower Devonian Moroccan phacopid, Wenndorfia planus. Nicely enrolled, and uniquely prepared in a tilted pedestaled fashion to show off its "assets," this trilobite was reassigned by Sandford (2005) to Wenndorfia from the species Parahomalanotus... which in itself was possibly mistakenly elevated to genus status. For those interested in some of the twitchy taxonomic tango see:
Sandford, A.C. (2005)
Homalonotid trilobites from the Silurian and Lower Devonian of south-eastern Australia and New Zealand (Arthropoda: Trilobita: Homalonotidae).
Memoirs of the National Museum Victoria, 62(1):1-66
Basse, M., & Franke, C. (2006)
Marine Faunen aus dem frühen Unteremsium (Unterdevon) des Givonne-Oesling-Antiklinoriums (Luxemburg).
Chatterton, B.D.E., Fortey, R.A., Brett, K.D., Gibb, S.L, & McKellar, R.C. (2006)
Trilobites from the upper Lower to Middle Devonian Timrhanrhart Formation, Jbel Gara et Zguilma, southern Morocco.
Palaeontographica Canadiana, 25:1-177
A number of trilobites came in the mail, with several more waiting at the post office and some in transit. First up is a Paralejurus dormitzeri
This fairly common Devonian corynexochid from Morocco does appear fairly often for sale, but a lot of them are the victims of quick and brutal preparation. This one has very good quality preparation, with some minor restoration on the lower right pygidium. Finely detailed with the eye lenses, terraced growth lines, and pedestaled to show the cephalic doublure. Only a few scribe dings, and measures close to 80 mm.
A cute and small Asaphus kowalewskii. Although I already have an example of one (semi-prone), this young holaspid stage specimen was too adorable to pass up. Some slight compaction between the third and fourth axial ring, but virtually no restoration of this stubby-eyed example of the species.
Hooray! Another winter prep project to keep from going bonkers from fossil hunting withdrawal. This is a relatively small semi-prone Asaphus lepidurus.
Until tomorrow when a few more trilobites join the collection...
On a grey, snowy day, Deb and I paid a visit to the annual London Rock and Mineral show. Shows like these are heavily dominated by vendors who specialize in minerals, jewellery, healing crystals, etc., but there are tables with other stuff as well, including space rocks, microscopic crystallization displays, the local rock club, and the local university's earth sciences department. Vendors specializing solely in fossils were uncommon, and one could encounter a few fossils among the sale items by the mineral specialists as well.
In terms of fossils, a good bulk of them are the typical fare of polished Moroccan orthocerids, polished Madagascaran ammonites, eminently displayable Green River fish from Wyoming, and standard trilobites (common Moroccan phacopids and proetids, mostly, and the usual flush of Elrathia kingii from Utah). Some neat stuff like shrimp from Solnhofen, petrified wood, and the like as well.
The real highlight was in speaking with two vendors, both fairly aged, who are still collecting, and with one collecting locally. There are certain names of collectors, sites, and species we know as we talk shop. It is a small world! One vendor actually knew Charles Southworth personally, so that was a local bit of history.
I didn't buy much, as there wasn't much of interest I wanted to buy (or prices were marked up far higher than what I could acquire them for elsewhere). But, I did buy two things.
A sealed, new copy of what is a kind of trilo-bible for NY collecting (with some significant overlap with similar species in Ontario). I already had the digitized copy of this in my rather robust trilobite book and article library, but sometimes nothing quite beats having a physical book. The photo plates are very nice, and I suppose it may be better to drool on paper rather than on a screen.
And the other purchase: cephalon of an Eldredgeops iowensis southworthi. I don't usually purchase fragments and partials, but it just so happened after all the conversation about Arkona and Charlie Southworth that I figured I'd pick up the trilobite named in his honour. These ones are quite rare to find in the Hungry Hollow Member (a collecting comrade managed to find a full roller of one last October, the lucky duck!). The sheer size of this phacopid is impressive, even in fragmentary form. It differs from the standard Eldredgeops rana mainly in terms of the highly tuberculate sculpture. I do have a small pygidium of one collected some years ago, but this seemed too special to pass up. The vendor I bought this from extended an invite to visit his shop up the highway, and maybe an opportunity to collect with him.
And that's about it this time. With ongoing labour strife with Canada Post, I have a few items coming that will likely be delayed for some while. So far, I am still waiting on some Milliput for restoration work, and two Russian trilobites to prepare (one a new species of Illaenid for me, and the other an asaphid I already have two examples of, and will probably prep and flip).
Until next time...