@Q36, first welcome to CCF. Second, surface staining can come from exposure to a variety of chemicals or even the environment. For whatever reason, one side was protected from exposure while the other side was not.
"If you climb a good tree, you get a push."
-----Ghanaian proverb
"The danger we all now face is distinguishing between what is authentic and what is performed."
-----King Adz
-----Ghanaian proverb
"The danger we all now face is distinguishing between what is authentic and what is performed."
-----King Adz























