M y golden comet "Trouble" has been laying thin shells since about July. She laid fine until then, but since July her eggs are almost always broken when I collect eggs. None of my other hens lay eggs like this, and have always had oyster shell available- so I know it's just her egg mechanism. She hasn't been laying for a while, taking a seasonal break. This morning I saw her in a nest box. Went out a bit later and this was in the nest box. It was firm. When gently squeezed, I could feel thin shell crackling inside. it didn't feel hollow, but I didn't want to squeeze too hard in case it squirted stuff at me. I cut both sides open, big mistake. The larger part had green liquidy stuff and smelled like what I assume is rotten egg. Never smelled that before, but yuck. Here are photos of what it looked like inside. She doesn't seem ill or anything, but I wish I had refrigerated it and sent it to Cornell. . I will if she does it again. Maybe I'll email these photos to Cornell and see if they have any info. I've checked other threads about this, and there doesn't seem to be much helpful information. Makes me wish I had a lab so I could solve the mystery. Any ideas on what this could be?