Fossil Forum

Looks like a egg has a shell, membrane, white area and a yolk. If it looks like a duck doe's it quack?? ( sort of a pun)

Looks like a concretion.

Concretion. They are also known as 'thundereggs' for obvious reasons. In weathered limestone/dolostone country they are often composed of chert.

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It looks like a type of dinosaur egg. I'm not a paleontologist but if that is not a petrified or fossilized egg, so then what is? It definetely to me is an egg. Good find definetely. I recently found one too, but mine is more difficult to know what it is because it looks like a petrified potatoe. Regards.

looks like a real egg to me also , pretty kool find

thundereggs have colour in them and rare for them to be a real egg shape like that one. https://www.google.com.au/search?q='thundereggs&hl=en-GB&rlz=1T4GIWA_enAU680AU680&source=lnms&tbm=isch&sa=X&ved=0ahUKEwinhf28ssPNAhXOq5QKHa74D7kQ_AUICCgB&biw=1344&bih=622

glad i popped in and seen that !!

AJ

Not true, aj. I have collected many many thundereggs in eastern TN limestones that look exactly like fossilized eggs. Colors vary by region; around here they are typically black inside white. Authentic fossilized eggs do NOT look like that.

OP, take your finds to a local rock club or gem/mineral show. Or to your local geology dept. They can id them for you. I know we all want our finds to be unique and valuable but internet experts aren't worth what you pay them. See someone you know is a geologist. And yes, I am a retired geologist.

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Minelab Excalibur II
Minelab Safari

The tipoff is this: what was the geological setting in which it was found? If it was in carbonate sediments such as limestone, it is a concretion, not an egg. Silicate metasediments are often sources of fossils but an egg would not have survived metamorphasis intact. If it was in nonmetamorphized silicate sediments or volcanic ash beds known to have produced fossils in the past, it still might be a concretion but "egg" is a possibility.