Determining whether eggs are fertile

Question

Lizzie eggs   QUESTION: We have a female bearded dragon about 10 yr old, and she has lived without contact with any other BD for at least 5 yr. Two days ago she laid 6 eggs, buried them all within an hour. We assume they are not fertile but if there is any chance that they could hatch we would be glad to get an incubator and wait 60+ days! Any chance they could hatch? Any tests we could perform? Attached is an image from 4:30 PM ET 2/25

ANSWER:   Those are unsusally long shaped eggs.  About the logest time a bearded dragon can retain sperm from a male is about a year, so if she has not had contact with a male in 5 years, they are probably infertile.  At her age, she should be checked by a vet to make sure she has passed all the eggs.
  I have found that infertile eggs, freshly laid have a yellow tinge to them, while fertile eggs are slightly pinkish.

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QUESTION: We decided to try to incubate them - maybe too cold for too long, but, when we unearthed them, the eggs were soft and have "waists". Originally they looked like Good N Plenty candy, but now they are slightly crooked. How will the eggs' appearance change if they are actually alive?

Answer
 I saw how elongated they were, and since she is an elderly girl, these could be weak double yolkers.  A fertile egg in damp vermiculite, kept at 85 F, and humidity at 70% should swell and stay white.  Fertile eggs will expand till hatching.  Then when hatching is about to happen the shells will soften and wrinkle, allowing the baby to tear through.
 Infertile eggs may harden and go yellow to brown, shrivel, or stay plump and never hatch.  Beardie eggs usually take an average of 70 to 100 days to hatch.