I ran a 4870x2, 4870 GS, and Supreme Lt in copper in 2010, surely these guys were made/casted in 2009 (raw copper production). Used them for about 6-7 months and there was no issue with the copper. And I ran dye

Only thing is the copper tarnishes brown BUT on the surfaces exposed to air, the "wet surfaces" were very nice and clean when I prepped them for sale.