Until the big, thick, white blanket of winter is yanked off, it looks like my adventures will be confined to what I can do indoors. Over the past year I've been gradually adding more fossil preparation gear, and although there are a few more items left on the list, it is coming along nicely.
Let's start off with a before and after picture of the space that I finally got around to clearing up:
Much neater. There's not terribly lots of space in my house, and the basement is largely dominated by exercise equipment. Still, I did manage to secure this corner of the basement. All I now need to complete the furniture is to get a second working surface to the right of the first one. All the necessary tools are in their rollout drawer or on the top. I'll need to develop a system to place the compressor in a better spot, with holsters for the scribe and abrader. A work in progress, but definitely an improvement!
This little toy may make sewing needle based prep a bit easier. The lenses swap out at different magnifications of 10x, 15x, 20x and 25x, and comes with neat side-mounted LED lights. These might actually be very helpful in the field for getting close to the ground and looking for tinier fossils.
And this arrived the same day as well. An OMAX 3.5x-90x trinocular scope with a USB-fed 3.2 MP camera. It took a ridiculous amount of time to assemble this as it came in a zillion pieces, and the instruction manual that it came with was for an entirely different model (and written in that transliterated Chinese that reads very awkwardly. It comes with 10x and 20x wide-field eye lenses, and a Barlow lens to permit working at a distance - essential once I get a blast box. I went with the adjustable boom as the scope needs to rest on the outside of the blast box glass. Looking through the eye pieces at the right distance takes some getting used to.
The scope came with camera software, but it was on a CD... and no Apple products come with a CD/DVD drive anymore. It took some sleuthing online to find the software for download. It will take some learning with the software and how to line up the specimens properly for photography. There is a pull-out stop that sends the light up through the camera lens mount, which cuts out light to the left eye piece. What I see through the eye piece is not what shows up on the screen, so some jiggering about is necessary. Pictured here is a fairly nice closeup of a Greenops trilobite that would be about an inch long, of which you can see about a quarter of it here.
This will be very useful for detailed preparation. It would not be useful to get too much closer than 40x-50x for that purpose.
All that remains now is to get the blast box, shop vac, and to work on how to vent it outside (maybe through the dryer vent). I anticipate my next blog post here will either be something to do with the fruits of preparation, or in a package of trilobites from Europe from a forum friend - whichever comes first!
Hunkering down to keep warm in snowy London, until next time.
So today I decided to spend part of the morning at that site near my house, the infamous "riprap hill" and associated pit. I've long suspected most of the rocks I split there were trucked in, and have confirmation of that due to the three different kinds of trilobite I've pulled from it (two in the last four months - Anchiopsis anchiops and Mannopgye halli).
I had been finding examples of rock from the Hamilton Group, Dundee Formation, Bois Blanc Formation, and the Amherstberg Formation. A good and wide range of Devonian age rocks.
As can be seen above, the usual assortment of brachiopods and a gastropod. My expectations were low as I'm running out of rocks to break after four years of scouring the place.
Ok, but what about this? I get the line by Morpheus in the Matrix in my head saying "what if I told you everything you knew was a lie?" So at first I was in disbelief: this must be a shell impression, not the impression of a trilobite pleura. But I've seen this before. In the Ordovician. Yes, it is a fragment of a Pseudogygites. The nearest Ordovican outcrop is 300 km away.
If I needed further proof, I flipped over this piece of shale and saw a fossil barely bigger than the head of a pin. Putting it under the microscope, it is indeed the cranidium of a Triarthrus.
Oookay, then. Confirmed: dumped rocks that span over 100 million years. From a field perspective, this is going to make things much tougher in terms of certainty over finds, but I suppose it means a veritable potential bonanza of finds spanning a much broader range of geologic history.
I was able to spend a solid two hours in the south pit at Arkona this past weekend. The rain went from drizzle to downpour, and as mucky and unpleasant as it might make a sustained outing, the weather this season has been so erratic and rain-soaked that it is nigh impossible to plan collecting trips around (unreliable) forecasts.
Still, I made it fairly well in what was mostly a surface collecting operation. The rain brought out the colours of the weathered out fossils very well, making their browns and blacks "pop" for easier spotting.
Weathering out of the Arkona clay, I spotted quite a few of these goniatites. On sunny days, at the right angle, the sunlight makes their pyritized surfaces shine and become easily found; in rain, they show up as dark brown against the Arkona shale's light grey. But these are all full specimens. I've arranged these in ascending order of size, and I was quite impressed to find such large ones when a lot of them tend to be hardly larger than the head of a pin.
Finding full Eldredgeops rana rollers is not unheard of here, but the place does get picked over so thoroughly that they certainly are tougher to find. This roller (pictured at the bottom) had its pygidium sticking up and my eye was immediately drawn to it. As finding disarticulated pieces are the norm, I was pleasantly surprised when it turned out this one was complete. Pictured above it is a small piece of fish plate.
This bumpy piece is a bryozoan. I don't find many of this particular type, and its constellatory arrangement reminded me of when I found that very rare bryozoan at the JD Quarry in June.
The amount of coral one has to sift through can be exasperating, but from time to time one encounters a nice piece worthy of putting in the collecting kit. In this case, a multi-cup example where the calyxes are very nicely articulated.
A collection of Platyceras spinosum. The one on the far left has still retained some of its stubby spines, while the one in the middle is a juvenile. One little fact about these gastropods is that they were coprophagous (they ate poop!), and so it is common to see them fossilized as being a symbiotic attachment to various creatures, particularly crinoids (although I do have one that affixed itself to a coral).
I always manage to pick up little goodies, even if I already have plenty of examples of these already. This assortment is heavily dominated by crinoid ossicles, some with cirra, but if you look closely you will find some tiny nautiloids, brachiopods, and the "button coral" Microcyclus on the upper left hand side.
And, finally, below is a short slideshow of some of the above finds under digital microscope at x75 magnification. In all, not a bad haul for two hours collecting in lashing rain!
Deb and I are set on our first trip to Blasdell, NY's world-famous Penn Dixie site. Two solid days of prying, cracking, and splitting - with hopefully enough fine trilobite specimens to show off, and a lot of matrix to play with in the winter to come.
Since my last post, I managed to make it out to Arkona two more times, as well as the Boler pit twice (finding my second specimen of a Paraspirifer acuminatus). I didn't manage to find anything all that spectacular, so will not be showing more pics of the same stuff you've already seen. But the temps are climbing back down to more comfortable and reasonable levels as autumn makes its stealthy approach ( the leaves, they are a-turnin'!). I am also about to purchase a Dremel stone engraving tool to practice freeing some trilobites that are embedded in matrix. This should be good practice for whatever big chunks of matrix I can bring with me from over the border.
But why not a few pictures in the interim? Here are some select images from the digital microscope aimed at some Arkona finds, and a confirmed Proetus alpenensis(?) - or crassimarginatus(?)
Just a closeup of a Bactrites nautiloid
Tentaculites are neat and taxonomically perplexing!
Goniatites up close and personal, an ammonoid. Not my best example, as I've been pulling ever more out recently.
Say hello to my little friend, the newly confirmed species of trilo in my collection, Proetus.
Why have I included this Eldredgeops rana cephalon fragment in the mix, pulled from the Boler pit and keeping company with a bunch of ne'er-do-well spirifers? Well, because of size. Although this is likely just a moult, this is proof of a rather big boy. Using a kind of averaged out ratio calculation for this species, I figure that the full size would have been about 3 inches, cranidium tip to pygidium tail. I exhausted the rock this one came from in search of just one other piece of the moulting, but to no avail. Alas.
Stay tuned in the weeks to come when I put up our finds from Penn Dixie, and possibly some first attempts at specimen prep! As always, thanks for reading!