isopropyl alcohol on coppor waterblock? help!

[Xraytom211]

ok im installing the waterblock on my gtx 680 tonight and i wiped down the copper surface on my waterblock by xspc with some isopropyl alchohol and there are all funny colours on it now!? is this good or bad. it refelcts aswell and i cant get rid o it? has it de iodized the copper? is it no good anymore? it look like there is oil on it HELP do i continue putting it on?

 

[popatim]

mix some salt and vinegar together and use that to clean off the mounting surface, then mount it. You only tarnished the block which was unavoidable in the long run anyways.