Ball Mason clear Quart Jar with veins of cold hot glass

Hi,
I have an old ball mason clear quart jar. On the front of it
it has Ball Mason as well as a vein of cold hot glass. What
terminology is used to describe vein of cold hot glass? Thank you.
Rob

 

The internal crack near the handles of a lot of Fire King pitchers is called an annealing crack but yours looks more like something was in the mold

 

Thank you for the information. Rob

 

Those veins of hot cold glass is smooth like the outside of the jar. I could not get my fingers low enough to feel inside to see if that was smooth or not inside the jar. I wonder if it could be within the glass. That can be answered if I can find a smaller hand like a child's hand whose fingers can feel inside the jar. Rob

 

It looks like a bit of crackle, which could be a cooling defect. Crackle can be intentional, but not in this case.

 

Thank you for the information. Really good knowledge. Thank you Rob