Every dinosaur that swam, flew, or walked on our planet, from the largest Alamosaurus to the smallest Microraptor, started out the same way: hatching from an egg.

Fossil eggshells can tell us much about how dinosaurs developed and evolved in ovo. We also know that most dinosaurs protected and nurtured their eggs rather than simply abandoning them, as had been originally thought.

This specimen is a fragment of Hypselosaurus eggshell from the Provence region of southern France. Recent studies suggest that the sauropod may have been a "small" titanosaur, measuring perhaps 12m (40ft) in length in adulthood.

Each specimen has been affixed to a 4x3" informational card that has more photos and information about the fossil.

"I would go to museums and say can I open your dinosaur egg? Can I just drop them on the floor and look inside? And they'd say no." ~ Jack Horner, Paleontologist

Many classic dinosaur books credit American George Olson with the first discovery of dinosaur eggs back in 1923 during an expedition in Mongolia. While Olson's find was the first recognized egg find, the real honor goes to 19th century French Catholic Priest Father Jean-Jacques Poech. In 1859, Father Poech came across the shell fragments of what he believed to be a giant bird. As it turns out, those eggs were really from Hypselosaurus.

Hypselosaurus was first described by P.E. Matheron in 1869 based on a selection of fossilized bone fragments. Matheron initially concluded the remains came from a huge crocodilian, but in 1890 Charles Depéret proposed Hypselosaurus was actually a sauropod dinosaur. The definition of Hypselosaurus has continued to shift over the years from a small to midsized sauropod perhaps 12m (40ft) in length to more current theories that may assign the remains to other, more firmly defined titanosaurs.

Fossil eggshells Matheron collected from the same site where he found the Hypselosaurus skeleton bits are notable as the first (non-avian) dinosaur eggs discovered. This specimen comes from the same region.

As you might expect, fossilized sauropod eggshells can be a little dirty. In preparing the eggshells for Age of Dinosaurs, we were presented with the challenge of clearing the debris that had built up, without damaging the unique surface of the shell and preserving fine details like the oxygenation channels.

Our initial experiments to clean the eggshells led to the mutual removal of debris and the erosion of the ridged surface of the fossil. We tested various solutions and tools, but the end results were abraded and lackluster shells.

To take things to the next level, we turned to the Journal of Paleontological Techniques and an article by Spanish paleontologists Sandra Val, Rubén García, and Domingo López titled "Preliminary Results on the Chemical Preparation of Dinosaur Eggshells."

This study details fifteen (15!) different methods for preparing dinosaur eggshells using a variety of chemical agents. In the article linked below, we cover the entire process.

📖 Keep reading "Fifteen Recipes for Preparing Dinosaur Eggs"