Without being there to actually see it I suspect your problem is either the clear lamination between the glass layers is discoloring, you have years worth of micro-pitting that can give glass a "dirty" look or a combination of both. Try Bon-Ami to clean the glass. That's what is used by professional labs to get glass absolutely clean prior to testing. If it's still "dirty" you'll likely have to replace it. Cleaning Glass.
Last edited by Tiny; 09/12/2014 2:26 PM. Reason: added link
Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.
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