Most dinosaur eggs are found in sandy shores of old waterways. They are positioned in clusters of 6-8 laid during Cretaceous period(146-66 million years ago). Anatomically, dinosaurs have two oviducts or ovaries connected with a tube where hard shelling occurs.

There are two main types of dinosaur eggs shapes/ structure: spheroidal and elongated. They can be subdivided into three types:
• Spherulithic egg shells have spherical patterns
• Prismatic egg shells is a mixture of spherical and prism patterns
• Ornithoid egg shells have biocrystalline upper to middle patterns

Egg classifications based on the type of dinosaur which laid them are:
• Sauropod
They appear in spherical to subspherical shape with very long thin crystalline component. They have spherulithic shells in structure. Most of this specie was discovered in Argentina
• Theropod
They include Troodon, Ovirator, Therizinosaurs species. Troodon appear to have elongated shape with ornithoid shell type(thin shells). Ovirator has elongated and elliptical shapes. They have unique nodes and ridges in the surface. Therizinosaurs have two types the Manning egg and Louie egg. They are spherical and elongated shapes. Most of this specie was found in Montana.
• Ornithopod
They are rounded with slight elongated shape. They have longitudinal ridges in the surface. Egg shells are spherulithic in structure. Most ofthi species are also found in Montana.

With regard to the behavior or manner of egg laying, here are some of the theories made by egg discoverers:
• Dinosaurs lay eggs one pair at a time
• Some of are laid in nests while others are in soil and debris
• Some dinosaurs warm eggs by their abdomens others use their throat and thorax.
• They can lay as many as 21-33 eggs in one nest.
• Eggs are carefully hatched. Shell openings are found on top layer which means hatching occurred upward.
• Dinosaurs eggs were protected by predators: smaller dinosaurs

The largest dinosaur eggs ever discovered originated from a titanosaurs. Titanosaurs are from the family of sauropods. They were about 18cm long with 5 mm shell thickness. They contained 5.5 liters of fluid. Another specie was discovered with a size of a football. Research revealed that it came from Segnosaurs or meat eaters in Asia. On the other hand the smallest eggs discovered were from prosauropods of South Africa. They were about 6.5cm long and 5.5cm width. The tiniest eggs found was from a theropod. They were 18mm long and 0.7 inch in width. The latest and best discovery ever made about dinosaur eggs was the body of a female dinosaur conceiving two eggs. Eggs look like pineapple sized potatoes.

Here are other additional facts regarding dinosaur eggs
• Studies on the real and actual color of eggs can be hardly identified since egg discoveries are already fossilized.
• The most expensive dinosaur egg for sale was sold for about $470. While the most inexpensive egg was at less than $200.
• During the Jurassic fever, a friend of Princess Diana paid 1400 pounds in exchange of sauropod egg at Bonhams auction.
• Patagonia, Argentina housed the largest number of sauropod eggs ever found in the history of mankind.
• Another breakthrough is the discovery of 6 intact embryos. The creatures had eloquent jaws , intact nostrils and peg shaped teeth.
• Researchers use CAT/CT scan (computerized axial tomography) to see what is inside the whole eggs discovered. In other cases, they used mild acid bath solution to slowly remove shell.