eggs with lumps and bumps

[violet]

My hens are laying eggs with hardened bumps, kind of like extra shell material, on them, usually clustered at one end. I haven't found the definitive reason, but am wondering about Vitamin D. Has anyone seen this condition or know what the problem is?

 

[joedie]

I've seen it posted on here before and I think the general concensus was calcium deposits.