1.18.2 latest version.
After testing, I can confirm that the cause of the blackening of the crock is the Sodium mod (single mod test), but I do not know the cause of the blackening.

I'll see what I can do about this, thanks for reporting!

Thanks for figuring that out, was wondering what was going on. Nosrick, let us know if you need some logs

Turns out I can't do anything about it, but Indium seems to fix this!

Give me a shout if you're okay closing this issue.