ID this… egg?

[astreck827]

No idea what this is. Eggs maybe? Or some kind of sponge? It’s in the underside of a rock in my display refugium.

 

[Impala67]

No idea what this is. Eggs maybe? Or some kind of sponge? It’s in the underside of a rock in my display refugium.

What are your tank inhabitants? How long has it been there is it soft to the touch or is it hard?

 

[threebuoys]

Looks similar to a conch or welk egg case in the wild. Do a google search on either. They can be pretty large in the wild, don't know about an aquarium.