Unusual Dinosaur Egg Fossils From China?

[Han.T]

Hi all,

On one of our regular outings we stumbled upon an old shop in Chinatown with the following egg fossils on display. The owner supposedly brought many of such fossils out of China many decades ago and they are now part of his prized collection.

The first two photos are of a nest of small oval-shaped eggs around 3 inches in length. The third photo is of a single egg similar to that in the nest, also measuring 3 inches length. Lastly is a different kind of spherical egg about 4 inches in diameter.

All eggs are on the typical red-mudstone that most Chinese dinosaur eggs are found on, leading to our suspicions that the oval-shaped ones may be of Protoceratops and the spherical one could be from Therizinosaurus. I am not entirely sure however as they also do bear some resemblance to Crocodile and Turtle eggs.

Can anyone shed some insight on what type of egg fossils these are? I would love to find out more on their oology, thanks!

[Han.T]

Here is another specimen that seems a bit dubious(was told it was a pair of Tarbosaurus eggs and they measure over a foot long), what do you guys think?

[Auspex]

They do have the texture of egg shell. I presume that they were prepped from the bottom, which would explain the limited extent to which they are revealed. As to species...???

[Han.T]

Apologies about the bad quality of the photos. The eggs in the first post do seem to have genuine eggshell, but I am still uncertain about what species/oogenus they are. The subsequent pair of large eggs(Macroelongatoolithus?) seems a bit too perfectly preserved, how do "eggsperts" tell if eggs like these are faked or real? This article here references a double egg specimen made up of both a real and a faked egg; to my untrained eye there is little difference between the two!

[MikeR]

I am by no means an expert on dino eggs but if I am not mistaken, it was discovered several years ago that eggs from the Gobi that were attributed to Protoceratops were in fact from Oviraptor.

Mike

[4circle]

[it's best practice not to reveal too much detail publicly about testing techniques because this allows fakers to design frauds with our tests in mind]. So, I'll try to answer your question generally:

As an analytical palaeontologist I unfortunately have a little too much experience of this...

Eggshells and eggs are quite easy to fake and also to 'improve'. Mixing clays and various adhesives produces a material that even to the expert eye can pass for the genuine article. This is distinctly different to trilobite fraud which often uses entirely synthetic resins which can be tested for quite easily. Another technique we're seen quite a bit of recently is the use of consolidants (these are chemicals which palaeontologists use in the field to consolidate and reinforce fragile specimens) to bind together clays into eggshell-like textures in the hope that a lab test will simply detect a chemical that could have had a legitimate use.

One of two definitive tests we use is to cut a thin section - this is a slice 30 microns thick (half the thickness of huuman hair or 1/3 paper thickness) which is so thin it can be examined in transmitted light with a standard microscope. real eggshell has a very distinctive structure, whereas bonded clay is amorphous just looks like grains stuck together. This is quite obvious in these two photos, I've chosen these from our material as no expertise is required to tell these two apart:

https://flic.kr/p/nyF8Yh

https://flic.kr/p/nR2aD7

If they are fossils this also allows us to determine the provenance - e.g. turtle eggs have very different microoological characteristics from those of dinosaurs. I'm happy to provide more details, but the differences are quite technical.

Another common issue is 'improvement' where broken eggshell pieces are engineered back together into a egg-shape. This 'egg' can be any size or shape the maker wishes, and this is very hard to detect. The example you posted the link to above is one such case. Eggshells are not smooth but actually have distinctive patters on their surface and with a microscope and a lot of practice it's possible to see how this correlates across joints and between pieces.

My advice on this material would be that unless it can be authenticated by an independent expert or analytical agency you may be buying a very expensive pile of clay and glue. A "certificate of authenticity" signed by the dealer or their company is meaningless (and highly suspect). Nothing short of a detailed expert appraisal or a full technical report detailing tests performed by an independent analytical company should be taken as any indication of provenance.

Hope that helps!!

[paleo1]

Here is another specimen that seems a bit dubious(was told it was a pair of Tarbosaurus eggs and they measure over a foot long), what do you guys think?

This is likely a fake. Sometimes they put a piece or two of real egg shell often tilted up to fool you. The white color is made to look like calcite and can be quickly removed unlike real calcite. The replica eggshell is composite (grout or resin) and under magnifier you cannot see the eggshell structure but instead see only fine grains of sand or plastic. You must take a couple pieces off with a pocket knife and not the ones pointed up to fool you. Also look for a grout edges all around the outside of the egg shell, not natural stone with good variation in color. This indicates placement of the cast item on the natural stone base with grout. One trick to hide this is use glue and powder from the natural stone but this will have a grain bigger than the natural stone.

[paleo1]

Hi all,

On one of our regular outings we stumbled upon an old shop in Chinatown with the following egg fossils on display. The owner supposedly brought many of such fossils out of China many decades ago and they are now part of his prized collection.

The first two photos are of a nest of small oval-shaped eggs around 3 inches in length. The third photo is of a single egg similar to that in the nest, also measuring 3 inches length. Lastly is a different kind of spherical egg about 4 inches in diameter.

All eggs are on the typical red-mudstone that most Chinese dinosaur eggs are found on, leading to our suspicions that the oval-shaped ones may be of Protoceratops and the spherical one could be from Therizinosaurus. I am not entirely sure however as they also do bear some resemblance to Crocodile and Turtle eggs.

Can anyone shed some insight on what type of egg fossils these are? I would love to find out more on their oology, thanks!

The upright eggs are likely Troodon, there were only two dinosaurs known to lay their eggs in this fashion. Troodon was very smart and their eggs required turning. Unlike all other raptors they also laid their eggs one at a time not in pairs.

[Han.T]

Thank you all for your insightful comments, I have learned a great deal about faked egg fossils from this! The upright eggs do indeed seem to match examples of Troodon, will look more into it.