Did you try to candle even if you can't see the duckling moving you should be able to see the air sac.Okay I tried to smell the egg but it has no odor. Can you smell a rotten egg through the shell? Are they are really that bad? I know if it gets broken it is horrible.
I have seen pictures online of eggs that look blueish= here is one:
http://www.google.com/search?q=duck...Xa6wHk8fD6BQ&ved=0CAUQrBE4QQ&biw=1024&bih=664
Well that was a lot longer than expected but it's an image on google that shows a duckling hatching. The eggs appear to have the blueish tinge too.