I have summer yellow Counter (http://GialloFiorito.com) tops. Approx 6-8 mos after installation, color changed. Veins darken to black with some discloration around sink. The fabricator has inspected twice and (http://maplered.com) cannot resolve the issue. Shield 611 impregnator sealer has been used. Water beads up on Counter (http://GialloFiorito.com) . Stumped!
