Vintage MCM Murano Mandruzzato Sommerso Faceted Art Glass Vase Read pls

Vintage MCM Murano Sommerso Faceted Mandruzzato Art Glass Vase. Measures about 8.25" T, 2.25" X 2.25". Has some issues. 1 chip on top outside edge, one on bottom. One side has, what I can only describe as, zebra pattern marking. I can't figure out what caused it, and it doesn't clean up with glass cleaner; however when it is wet, it disappears. I can't feel it by touching it. It is a mistery. See close-up. Listing and template services provided by inkFrog