Is this a rotten egg?

[pntdhorses]

I’m currently letting my broody hen lay on Mandarin Duck Eggs. I’m guessing this one is rotten and am ready to toss it. No other eggs look like this. It is discolored and has dark markings running throughout. Am I correct in assuming that?

 

[Sagey_7878]

Yes, throw it out. If you’re a bit unsure, you can candle the egg using a torch in the dark. Good luck!

 

[Chick-N-Fun]

It looks rotten to me. Candle it for sure, but then dispose of it. It could compromise your hatch. GOOD LUCK!