Separating Grades?

Originally Posted by PinkFloydEffect

When I grinded into it with a bench grinder it did not show red/orange. The bolts were non-magnetic so I figured they are aluminum as well

The outer silverish layer is softer than the copper, when you hit it with the grinder, it ground off some of the copper metal & at the same time, smeared the silvery tin (or nickle) over the copper face & that made it look silvery again.

The bolts were stainless steel. Because of how they look I think theres a 'steampunk' interested in them somewhere.

You lost some easy $$ there, not much, but easy $.



Bugger.