Vintage CHANEL Sunglasses 5130-Q Rectangle Frame Leather Chain in Black & White

90’s Y2K vintage Pre owned with copper oxide present at the chain area and within the screws of the arms making them a bit difficult to open and close. Unsure if there is a hack to clear up the copper oxide. See close up pics of green/blue areas. One arm hinge can us tightening (see last 2 pics at differences) There is also yellowing of the white areas on the glasses Lenses have normal light scratching 100% AUTHENTIC CHANEL