Taking stock – Merry Christmas, but never mind the R, the Y and the I…

Santa is having a small Coroniceras sp. (left) and a Grammoceras thouarsense (right) leaned against his knees. Ravenscar in the background.

Santa is having a small Coroniceras sp. (left) and a Grammoceras thouarsense (right) leaned against his knees.
Ravenscar in the background.

Well, it’s that time of the year again, time for looking back, taking stock…
I often get asked, when the book will be ready…
2014 has been an extremely busy year for me professionally, with the effect that I
did not have much spare time to work on the book, and I’ve been to the UK only once
this year for collecting (strong withdrawal symptoms…).
Nevertheless I tried keeping up the work, doing at least 1 blog post in a month,
photographing and writing, though I’m not entirely happy with the progress,
but what can you do, the money has to keep coming in…and there are also limits,
how much time you can spend on the computer.
Short answer : It will probably take another year to finish all material,
so I need to look at 2016 as a rough estimate for publishing.

On a lighter note, on that one visit we met old and new friends,
photographed some stunning new specimen and became a fan of the lowest of the lias.
It was the 25th year we´ve been coming to Yorkshire and it continues to feel like
home from home, we can´t wait to be back in 2015 (hopefully at least twice !).

I have a few days off now, so I sat down before my drawers and looked for what genera
we have not covered so far (and the names mysteriously arranged themselves in a certain order) :


Yet more :


Riparioceras (synonym)
Incidentally also :
Schlotheimia (redcarensis)
Schlotheimia (angulata)


Nodicoeloceras (incrassatum/crassoides)
Dactylioceras (the ones we have not covered yet)




Harpoceras (subplanatum)
Yet more :


Nodicoeloceras (puteolum)


Yet more :
Rakusites (synonym)


By now of course you´ve got the message 🙂 and you probably also noticed that
I had to include some that we did in fact cover or might not even occur in Yorkshire
(look in the R´s)and that I did particularly struggle with the I and the Y´s
(there´s just no species names starting with those letters in the lias…)
but there are also some that did not fit in :


Liparoceras, Oistoceras :
We´ll have a lot of fun with these, including Androgynoceras, heavy stuff, and a
fellow countryman to thank for that…
Psiloceras, Caloceras, Coroniceras, Vermiceras, Alsatites  :
Some of the earliest lias ammonites, very interesting stuff, but so difficult to ID
when they´re small…
Crucilobiceras, Xipheroceras, Platypleuroceras, Bifericeras, Phricodoceras :
Finally – Spiny, spikey cephalopods !


Grammoceras, Phlyseogrammoceras  :
Together with Haugia and Harpoceras subplanatum the last of the Hildoceratidae
we´ll have to cover


Epophioceras :
Looks like an Echioceras, but seems to be related more to Asteroceras…


Leptechioceras :
A rare, almost smooth  member of the Echioceratinae


Catacoeloceras (crassum, raquinianum) :
Real “Fat Dacs” – we´ll have to work out their differences to Nodicoeloceras


So you see there´s still a lot to be done, chiefly in the Psiloceratidae, Arietitidae,
Cybitidae, Polymorphitidae ,Liparoceratidae, and we´ll have to finish off the
Dactylioceratidae and the Hildoceratidae – and that of course guarantees
that you´ll see some more blog posts next year !


In terms of visitors of the blog, it was another great year, getting close to 40.000
views in total,  about 15.000 this year. In terms of geography I guess by now we´ve
had visitors from most countries with Jurassic deposits, all though readers from
Greenland stubbornly refuse to visit 🙂 :


All time visitors by geography - not many white spaces left !

All time visitors by geography – not many white spaces left !


Not on the top 22, but all the same : Seasons greetings to a friend reading these pages
doing a gap year in Cambodia.


With best wishes for a peaceful, happy time for you and yours, wherever you are.


The Whitby Ammonite or a Whole lot of variation…

2 large D. commune adult specimen - both 10 cm - as large as they come !

2 large D. commune adult specimen – both 10 cm – as large as they come !

If there is one ammonite genus that is typical for the Yorkshire coast, more specifically for the coast around Whitby,
it has to be Dactylioceras. Do a search on UK ebay for “Whitby ammonite” and what you get is at least 50 % Dactylioceras, in natural form or sliced and polished…

The Whitby Town coat of arms (fuimus et sumus – we have been and we are – quite fitting)  bears 3 Ammonites, most likely Dactylioceras, with snake heads attached to commemorate the legend of abbess Hilda (see also link).

This all of course is due to its abundance on this stretch of coast, when walking on a beach where the cliff exposes the upper toarcian beds of the lias,
there is almost no way you cannot find a Dactylioceras (fragment), if you keep your eyes open…

A very worn pebble with a Dactylioceras sp. on Robin Hoods Bay beach

A very worn pebble with a Dactylioceras sp. on Robin Hoods Bay beach

In this blog post I´d like to introduce you to the 2 most common species of Dactylioceras : Dactylioceras commune (SOWERBY, 1815) and Dactylioceras athleticum (SIMPSON, 1855).

For the main comparison I´ve chosen two similarily sized, mid size ammonites (each about 7 cm) :

Direct comparison between D. athleticum (left) and D. commune (right), both about 7 cm.

Direct comparison between D. athleticum (left) and D. commune (right), both about 7 cm.

So what differences are there ?

Whorl section : First of all, D.commune has a whorl section that`s as round as a circle, while D. athleticum´s is more oval. I’ve re-prepped these two specimen especially to show this characteristic.

Ribbing : With D. commune the ribs run straight or just slightly convex across the venter, while with D. athleticum the ribs cross in a much more convex way, sometimes almost angled. With D. athleticum, ribbing is much finer on the inner whorls, and the rate of ribs/whorl does not change much on the outer whorls. D. commune has more coarse ribbing on the outer whorls, and finer ribbing on the inner whorls.

Both D. commune and D. athleticum occur in the commune subzone of the upper toarcian, in the Main Alum shale beds, D. commune in the lower part of the subzone (commune biohorizon) down into the Hard Shales (beds 49-54, approx. 15.9 m),  D. athleticum in the upper part (athleticum biohorizon), beds 55-59, approx. 2.8 m.(at Whitby according to K.N.Page in “British Lower Jurassic Stratigraphy”).

The maximum size for these 2 species seems to be around the 9-11 cm mark, with D. athleticum usually a bit smaller, but finding one of this size is quite rare these days. Adult specimen develop a constriction at the mouth border, which is mostly invisible on the surface of the shell, only showing clearly on the internal mold when the shell is removed. As seen on the D. athleticum above, there are some very fine ribs that mark the very end of the adult shell, when preserved.

So far, so good…

Now consider these ammonites :

More ribs, less ribs, round whorl section, oval whorl section, they all do look different from the two above ammonites that I’ve shown you as characteristical for the species, but are they different species or is it just whole lot of variation ?

These were not taken from in-situ off well-defined beds, but collected from the more or less wave rolled cliff debris on the beach, as most of us collectors do, as most of previous centuries’ collectors have done.

The answer probably is : Most of it is just natural variation within a species, with some you can take established species as a reference point and call them e.g. Dactylioceras cf. athleticum (cf : latin confer, compare to) . With some of them, if you don´t really know which bed they come from, it´s sometimes best to just call them Dactylioceras sp. – until you find another one in a defined bed.
Too little work has been done to really identify bed-by-bed variation of the Dactylioceras genus – imagine what could have been done in this regard when the big Yorkshire coast alum quarries were dug in the 18th and 19th century…

Saltwick Bay at low tide - Black Nab at the water line, the disused Alum works in the left background

Saltwick Bay at low tide – Black Nab at the water line, the disused Alum works in the left background

We’ll continue looking at the Dactylioceratidae on the next posts…


The colours of the rainbow or Right time, right place…

Peronoceras sp., close-up of iridecent shell remnants

Peronoceras sp., close-up of iridecent shell remnants

In some rare occasions, a little bit of the original shell of an ammonite is preserved and shows all the colors of the rainbow due to an effect called iridescence, thin film interference on the fine layers of shell material.

On the Yorkshire Coast, this is very rare and mostly seen only on Dactylioceratidae, probably due to certain environmental conditions (e.g. shell structure, lack of oxygen, composition of sediment,…) during the time of fossilization in the upper toarcian that were not prevalent to that extent during any other timeframe.

Dacytlioceras commune, 7 cm, with iridescent shell remnants

Dacytlioceras commune, 7 cm, with iridescent shell remnants

Of course, you have to lucky enough to find the ammonite, before the sea catches it – rolling around in the waves very quickly destroys the fine shell layers.

The sensitive patches on this Dactylioceras commune that I found freshly fallen into a dry heap of cliff debris at Hawsker at low tide some years back would have been destroyed quickly if the  tide had reached it 4 hours later – right time, right place – that mix of luck, experience, right choice of place and more luck that can make a collecting day successful.

Happy hunting,


Summer 2013 on the Yorkshire Coast

Summer on the Yorkshire Coast

Summer on the Yorkshire Coast

You may have guessed from my long absence from this blog : We spent a very nice 2 1/2 weeks of summer holiday on the Yorkshire Coast…

 On the one hand collecting in summer is very nice : You don´t have to wear thick waterproof clothes and heavy wellies, which easily takes away a few kilograms of weight that you don´t have to carry around with you (you add those again with your supply  of drinking water…), hours you can spend collecting due to available light are longer,
the general feeling is lighter and just – summery.
 On the other hand, there are more people around (allthough I usually hardly meet anyone when I go out collecting alone) – and finds are generally less frequent.

We´ve been meeting a few old friends again, made some new friends and some of them brought some truly, truly gorgeous ammonites for me to photograph.

I will not show them here, they´re for the book, but I can tell you there are some that I have not seen anywhere else in size, rarity and beauty ! (tease, tease…)

Adrian, Tracey & Bernie, David, Andy  : Many many thanks, you´ve earned your copy of the book, this is for you :

Happy smiling green seamonster !

Happy smiling green seamonster !

On a hot summer´s day I´ve been to Redcar for some collecting for the first time (only 1/2 hour quick search of the reefs : but I´ve found 3 identifiable segments of ammonites in this short timeframe which shows the potential of this place, I´ll be back…) and more photographing of local lias ammonites, but I was informed I could not use the photographs for the book when I had returned home, so this is for you (you know who you are !) :
Unhappy green seamonster !

Unhappy green seamonster !

Collecting wise, it`s been a mixed bag :

Flattened D. semicelatum and Tiltoniceras

Flattened D. semicelatum and Tiltoniceras

I´ve found many lower toarcian (unflattened) Dactylioceras tenuicostatum/semicelatum nodules, but a lot of them were disappointing when I opened them at home.
I found a rare D. clevelandicum, that another collector probably tried to beach prep and broke the outer whorl off, but I´m going to rescue the inner whorls.
The paltum subzone at Hawkser Bottoms

The paltum subzone at Hawkser Bottoms

I´ve been looking for the paltum subzone of the lower toarcian for some bedwalking and a chance of finding a Protogrammoceras paltum
(which I have not seen from the Yorkshire coast yet), but no success…
A puzzle of an Amaltheus stokesi...

A puzzle of an Amaltheus stokesi…

I picked up some puzzles like this close to 8″ Amaltheus stokesi…
Eparietites impedens as found

Eparietites impedens as found

One of the better finds this summer certainly is this 8.5 cm / 3.25 ” Eparietites , which nicely leads on to what´s up next :

The stage is set for the Asteroceratinae :
The stage for the Asteroceratinae ist set...

The stage for the Asteroceratinae ist set…

When I returned home from the holiday, temperatures were still very high, so when given the choice of photographing in my litlle study under the roof
at 30+ °C or prepping in the cellar at 20 °C, you know what I did…

It was just too hot and I guess this little live octupus I “met” sitting in a shallow puddle (the octopus, not I) while hunting for his ancestors felt just the same :

An octupus in a shallow puddle...

An octupus in a shallow puddle…

I tried to re-setlle it to a depper puddle since high tide was out for some more hours, but he stubbornly suckered itself to the ground and shot some ink at me
so I waved him goodbye and hoped the seagulls would not find him…
Temperatures are now back to normal at around 20 °C, so please excuse me, I´ve got some photographing to do…


A view through the chambers or Translucent ammonites

On the Yorkshire coast, most ammonites are most usually preserved mud-infilled or pyritized. Calcite preservation of a significant part of the whorls is relatively rare, but does occur occasionally, in my experience for example with

  • Psiloceras
  • Arnioceras
  • Euagassiceras
  • Pleuroceras
  • Eleganticeras
There are rare calcite preserved ammonites where the calcite is so translucent that you can almost look through it – I´d like to show you 2 examples :
The first one is a Psiloceras erugatum from the glacial drift (more on the lower lias ammonites from the glacial drift later) :
Psiloceras erugatum, 3 cm

Psiloceras erugatum, 3 cm

I photographed it against the light on my light table and pulled up the contrast in Photoshop to maximum to show the most of the translucent chambers.
The second is an Eleganticeras elegantulum that you might have seen earlier in one of my Christmas postings on the UKGE forum,
the resemblance of the sutures with Christmas trees was just too tempting…
Eleganticeras elegantulum, width of ammonite 4 cm

Eleganticeras elegantulum, width of ammonite 4 cm

With this one I did a little HDR setup, photographing it with a number of exposure settings and combined the pictures with a software later to capture the maximum dynamic range.
Of course beside the right preservation you also have to prep the ammonite completely free of matrix to see the light shine through – with the two examples shown I was lucky with the Psiloceras, it “jumped” off a multi block matrix free, the Eleganticeras was a lot more work involving air pen, diamond cutter and air abrader to remove all the matrix surrounding it without braking the fragile calcite inner mould.

20 posts or Who photographs the photographer

My little studio

My little studio

20 posts so far – that calls for a little excursion into photography and some reflection about my general workflow…
As you can see, this is my little studio where I photograph the fossils, with the “ensemble” of the Amaltheidae post still present.
It´s just a little Novoflex macro table, that I´ve put onto another table to reach comfortable working height. There are 2 flexible lamps with 5400 °K permanent light from above and another from below the slightly transparent table to provide a little contour light from below. There´s another led spot clamped to the table if I need it for a special spotlight etc. In front of the table I have positioned a sturdy tripod with a 3D geared head that holds the camera with a 150 mm macro lens which gets me to 1:1 size if I need to.  The geared head makes precisely framing the shot very easy, I find it a lot more suited to the task than a normal ball head. Depending on the size of the fossil I photograph, I move the tripod closer or further away from the table – the maximum size fossil I can do with this kit is about 30 x 30 cm.
If I photograph fossils for any post I´m planning, I will always do a lot more pictures than you actually get to see in the post. One reason is that I obviously do several different photos where I vary lighting, sharpness points, positioning of the fossil etc to get the best shot possible. The other reason of course is that I do not photograph only for the post – there are a lot more detail photos and shots of additional fossils that I get to be used later for the book !
I normally research the ammonites I´m planning to write about first, so the text usually comes before the pictures.
For writing the text I use a software called Evernote (it´s a free editor that saves the texts etc in the cloud) – It allows me to continue writing on my texts even if I´m not at home or not at my main computer.  Once the text is about ready, I select the fossils from my collection and do a photo session. Today´s photo session for the Amaltheidae took about 5 hours (while outside a thunderstorm with torrential rain & hail was going on…).
As the thunderstorm subsided, I switched my computer back on and began editing the photos. I run the pictures through a software called DXO first – it does a lot of automatic corrections for colour, white balance, sharpness, lens distortion etc for me. After that is done I do the masking, cropping and combining of pictures in Adobe Photoshop. If the picture will get used in the book I save it uncompressed for maximum quality in Photoshop´s own format so I can later use it without further problems in Adobe InDesign, the publishing software I´m going to use for the book. If it gets used in the blog as well, it will be re-sized for web use, marked with a copyright notice (If you like my pictures and would like to use them – contact me) and saved as a jpeg file, in a setting optimized for both size and visual quality of the picture.
Once text and photos are complete, I upload the picture files to the WordPress media library, add any pictures comments and paste the text for the new post from Evernote into the WordPress editor. I then add the links to the pictures in the media library, do a final spell & visual check – and publish the post !
This workflow has worked quite well for me so far, I feel that writing the blog posts gives me an intermediate goal that continues to drive my work for the book.
With over 2000 views to date (not much for a blog, but this is also a very specialized topic with a small target group), you readers out there seem to enjoy it as well
 – thanks for reading, wherever you are  !

Blog visitor statistics 07.07.2012

Blog visitor statistics 07.07.2012

My little red book or How I keep track of my finds

This is my little red book. I use it to keep track of all the finds I make during a collection day. Not when I´m out in the field (my memory is not that bad yet), but when I unwrap the fossils in the evening. I jot down the date, every fossil I found, it´s size, where I found it, any further interesting facts, since March 1991.

My little red book

My little red book

In the last couple of years, after digital cameras became affordable, I´ve also made a picture of every fossil I have found to keep a photographical record of what the fossil
looked like before I prepped it. When later you have to e.g. remove the matrix of the fossil for whatever reason, you can still reconstruct what it looked like originally.
Digital pictures cost nothing unless you have them printed, so I have a database of fossil pictures on my PC´s hard drive (and I do backup regularly).
Digital pictures also do have the nice feature to tell you their “date of birth”, i.e. the creation date of their file from their so called “exif” (for exchangable image file format) data. If you set the date on your camera correctly (!), you can use this information embedded in the picture to “find” every picture you made on a specific date on your computer´s hard disk. Together with the notes from my little red book, that makes it very easy to later on put the right information on the label of the fossil in the collection.
And since I know that you like those before / after prep photos, here are two sets of them…
Crucilobiceras densinodulum, as found

Crucilobiceras densinodulum, as found

Crucilobiceras densinodulum, prepped, 5.5 cm

Crucilobiceras densinodulum, prepped, 5.5 cm

This Crucilobiceras densinodulum was found on July 13, 2008 at Boggle Hole.
Amaltheus margaritatus, as found

Amaltheus margaritatus, as found

Amaltheus margaritatus, prepped, 7 cm

Amaltheus margaritatus, prepped, 7 cm

This Amaltheus margaritatus was found on March 29, 2012 at Hawsker Bottoms

The importance of colour or the absence of it

When collecting fossils, especially in a beach environment like the Yorkshire coast, where you often have to deal with a huge variety of different rocks from different layers, sometimes intermixed with all sorts of glacial drift, recognizing the fine differences of colours of the rocks is of some importance – it helps you pick out the rocks that (from experience) most likely contain fossils, even if they don´t show on the outside. For example when you´re red/green colour blind you´ll have more difficulty picking out subtle greenish shades of some lower liassic rocks.

Rock colours on the beach, a toarcian mudstone in the middle

Rock colours on the beach, a toarcian mudstone in the middle

As a collector I find colour equally important in identifying fossils and judging their provenance. Consider these two ammonites :
Two ammonites in black & white

Two ammonites in black & white

Of course I tricked you here : I intentionally converted the photographs of the two ammonites to black and white, even then I had to modify the exposure of the second picture somewhat to make it look more than the first one.
Here is what they really look like :
Two ammonites, natural colour

Two ammonites, natural colour

What a difference ! The left ammonite looks very much like a Yorkshire one now, while the right ammonite which is preserved in a strikingly light grey marl is actually from near Cingoli, Italy (specimen swapped against some Yorkshire material with an Italian member of the UKFOSSILS forum – thanks again !).
I guess one of the main reasons why many professional palaeontologists in their publications almost exclusively use greyscale photographs is just that : It eliminates colour variations. Sometimes fossils are even coated in white ammonium chloride smoke to further eliminate potential reflections, translucency, and greatly enhace surface detail.
This way you make specimen more comparable with ones from other areas, removing the unwanted effects of colour due to different preservation.
Other reasons may include the relative simplicity of the B/W photographic process compared to colour and the past cost of colour printing.
Now are the photographs in my book going to be black and white ? No – this is not going to be a book fulfilling all scientific standards, I want to show colour differences, I want to show you what the matrix in the luridum subzone looks like compared to the maculatum subzone, the golden shine of a pyrite ammonite, the deep black of a Gagaticeras´shell, or the chocolate-brown of a Yorkshire Zugodactylites. While the effects of whitening the fossils using ammonium chloride can have a dramatic effect on visibility of detail, it adds huge complexity due to necessity of a lab. Digital photography has eliminated many difficulties in the colour process (and printing in colour is not as cost-prohibitive as it used to be), but it has brought new ones as well – more on that later…

Ammonite photography or Views of a Fossil

For the book I´m of course looking for some of the best Yorkshire lias ammonite specimen there are !
Of the approximately 220+ species known (and this is still somewhat of a moving target, i.e. I´m still finding new ones  in literature that I have not considered yet, but I might also have to get rid of some from my list since they’re only synonyms)  I boldly (actually, that´s pretty much verified) estimate that I have about 50 % in my collection (and this in itself is a moving target as well : as I´m looking through my collection and researching the species I regularly find species I never knew I had !) . Now some of these are close to perfect specimen that probably need no other one to complement them for the book. Others are just fragments, badly preserved, too small, too large, you name it,  where I´m looking for other collectors to possibly fill the gap and allow me to photograph their prized specimen.
But this might not always be possible, for example when you don´t trust me to give your ammonite back after borrowing, you might fear it gets lost on the way, you´re living too far away (or I for that matter…), our schedules are impossible to get to overlap, you´re not eager to show me your whole breathtaking collection, you want serious money for allowing me to photograph your specimen or whatever other reason you can think of – but you might yourself be very capable of photographing an ammonite and willing to e-mail me the results.
So what I´m I looking for in terms of photos ?
  •  They should be tack sharp and normally exposed
  •  As many mega pixels as possible, minimum 6
  •  The ammonite should almost fill the frame
  •  Please use a light (preferably white) solid neutral background, no patterns in the background  please
  •  Use smooth even lighting, preferably one light from upper left, another one from lower right to lighten up the shadows
  •  Do not use flash unless with a soft box
  •  Do not use sunlight unless you use a reflector to lighten up the shadows
  • Do not use any software to modify, e.g. filter, sharpen etc the picture, I will do this for you.
  •  I can work with jpeg, tiff, dng, nikon raw (nef) picture formats
  • Do let me know what type of light you used, and which camera/lens combination you used
  • Please do not use anything like ammonium chloride to whiten your fossils, I´m looking for the “natural” look.
What I will do with the picture is this :
  •  Correct any potential color cast, lens distortion
  •  Slightly sharpen the picture
  •  Modify contrast, tone, color as necessary
  •  Isolate the ammonite from the background
  •  Give it a dropshadow to avoid the “cut out” look
What views am I looking for ?
A picture says more than a thousand words, so here it is :
Amaltheus subnodosus : Side view, keel view, aperture view (from left)

Amaltheus subnodosus : Side view, keel view, aperture view (from left)

I realize that depending on how the ammonite is prepped, an aperture view might not always be possible.
Side view and keel view are nevertheless essential : You cannot safely identify an ammonite if you only see the side view.
Other rules ?
  • Yorkshire ammonites only
  • I will accept Holderness coast and Cleveland 🙂
What will you get for your efforts ?
  • If I do use the picture of your ammonite in the book (regardless if I photographed it or you did) you will get a sincere “thankyou” and – of course – your very own copy of the book, with or without my autograph 🙂
  • In the description I will of course mention the collection the ammonite comes from, or not if you prefer.