Cracks around rim jets on toilet bowl

[Poiuytr]

Hi guys. I noticed when I was cleaning the toilet the other day that there are some large cracks just under the rim jet area of my toilet bowl. The toilet itself is old, I've not noticed it before, but I dont usually go looking inside the toilet much, just pop some bleach up there etc. The cracks seem to be quite smooth rather than jagged, though you can certainly feel the raised nature of the crack area - the water on flushing doesnt touch them much.

Am hoping you excuse my ignorance here - could these cracks have been here for years or do you think they have developed over time? I presume if this is a problem then I will have to replace the toilet bowl which is a back to wall unit. Is this a big job (I would get a plumber in for this) and how much would you think this would cost (roughly).

Apologies for the basic questions and thanks for taking a look.

 

[ShaunCorbs]

yes could of been there years it’s only a folded edge so it can crack structurally it should be fine just keep a mental not on
It

 

[Poiuytr]

yes could of been there years it’s only a folded edge so it can crack structurally it should be fine just keep a mental not on
It

Thank for coming back. Really appreciate you taking a look (sorry, thought I’d replied yesterday but doesn’t look like I hit the send button)