Anomalous Sample from the Wealden Beds at Hastings, Rock-a-nore, UK.

[blackdanter]

Hi folks,

 

This is an anomalous specimen from my collection.

 

The location is early Cretaceous, around 140 million years old.

 

I've never found anything else quite like this at the location before or since (I collected it a few years ago). It has the appearance of being blob or pancake of material. It's composed of hard clay pea sized matrix with a soft clay infill. One side has an ironised layer which looks as though it covered the whole thing at one time. Under a lens, the soft clay matrix is packed with really tiny fish teeth, spines, scales and bone fragments. The intriguing thing is the larger fragments, which are scales and bone. You do find assemblages of fish scale/bone, shark teeth/spines and reptile bones at the location but these are usually on the surface of beds of sediment (not in a 'pancake' like this. This material is not even remotely similar to 'bone bed' material which occurs 4 miles East along the coast at Cliff End (the tides here push material Eastwards),

 

There are obvious bits of small broken bone (shards). These have the appearance of the shards left over when your dog has destroyed a bone. In addition to that there are other bits which appear 'polished'. I can't decide whether these are broken teeth or somehow polished bone. To be honest the whole specimen feels like fossilised animal 'up chuck' of some sort.

 

The edge on the left of this image shows the ironisation layer, this edge is also covered in quartz type crystal material. Quartz infill/crystals are quite common at the location in ironised nodules.

 

 

A fish scale and two bone fragments or teeth. One is conical and points upward and one looks like a piece of rib except one end has cellular structure whilst the other end is solid. At the top of the image is a small damaged croc tooth.

 

 

A closer image of the anomalous bits. They don't look like any teeth I've come across before. All of the black 'peppering' is tiny fish teeth, broken spines and a few tiny scale fragments.

 

 

The second anomalous bit. Polished bone or tooth? I originally suspected croc tooth but the shape is really odd, elongated peg like would be the best description but the polished surface is weird looking to me (like a piece of polished dinosaur bone you might see at a gem stone sellers).

 

 

 

Another piece of bone poking out. I have recently started exposing this. There are a couple of other 'suspect' areas i also need to investigate at some point.

 

 

Any thoughts/observations appreciated.

 

[FranzBernhard]

Has the "ironization layer" anything to to with the rest of the specimen, genetically speaking? Or is it pure chance, that this specimen has one?

I see, you think, that layer covered/surrounded the specimen completely at one time in the past.

What does the back side look like?

Franz Bernhard

[blackdanter]

1 hour ago, FranzBernhard said:

Has the "ironization layer" anything to to with the rest of the specimen, genetically speaking? Or is it pure chance, that this specimen has one?

I see, you think, that layer covered/surrounded the specimen completely at one time in the past.

What does the back side look like?

Franz Bernhard

Hi Franz.

 

If anything, that layer may have helped keep the thing together or protected it from weathering.

 

Here's an image of the other side. You can see half of the layer remaining and folding over the left hand side which has quartz on that surface. 

 

[FranzBernhard]

Thanks!

You have mentioned "ironised nodules" with quartz infill. Are these concretions of some sort? Is something in addition to quartz inside these nodules?
Franz Bernhard

Edited May 16 by FranzBernhard

[blackdanter]

11 minutes ago, FranzBernhard said:

Thanks!

You have mentioned "ironised nodules" with quartz infill. Are these concretions of some sort? Is something in addition to quartz inside these nodules?
Franz Bernhard

 

The ironised nodules are usually often infilled with mudstone or quartz. Some are hollow and, every now and then, some have formed around fossils, usually fish remains. 

[blackdanter]

11 minutes ago, blackdanter said:

 

The ironised nodules are usually often infilled with mudstone or quartz. Some are hollow and, every now and then, some have formed around fossils, usually fish remains. 

Here's an example of fish remains from the location. The matrix is ironised material and mudstone (very hard). This is the articulated rear gill section of a Sheenstia. One side of the animal is quite eroded but that under the mudstone should be nicely preserved when prepared.

 

[FranzBernhard]

Thank you!

 

Now there is some more info to ponder the origin of this specimen. Your hypothesis, that your specimen is fossilized "up chuck" seems plausible and also consistent with the ironised crust.

 

From what animal could it be? All those "clay pebbles" suggest, that it was (also) a bottom feeder able to crush bone. A rather big one. Is the "meal" consistent with any known large and (partly) bottom feeding animal of that time? All this are just wild guesses and I am very probably plain wrong. But this does not matter!

 

Hopefully, more knowledgeable people than I will comment soon ! Thanks for sharing this highly interesting specimen.

 

Franz Bernhard