OrganoCup External Finish

I've spent quite a lot of time trying to apply a finish to the outside of the cup. I've been using Platinol to try to oxidize the surface to give it a grey metallic finish. Unfortunately, for some reason, despite a lot of cleaning and sanding of the outer surface, I've been unable to get full coverage of the cup. I got a lof of flaking and uneven coloring of the surface. I the end, I decided to make a virtue of the blotchiness of the surface and here are the results.

 

The inside of the Cup needs another sanding with Scotchbrite...however, this is what it looks like at the moment;