"Las Ollas Series Tres" by Amado Maurilio Pena Jr. Signed Numbered Print FOXING

Numbered 8 of 30 and dated 1970. The image itself is bright and crisp, but the white border has EXTENSIVE DAMAGE: what appears to be foxing or age spots all the way around. The included receipt from a Houston art gallery in 1980 says the piece was "museum mounted." I think it's a screen print, silk screen, or serigraph: the blue is saturated; the browns and golds are almost sparkly. Under magnification, there are no dots. 

Please look at all the photos. Framed size 14.75" x 18.5"; interior dimensions are about 8" x 12"