I saw a Truck driver polishing his bull bar whilst his truck was getting unloaded, and his alloy bull bar lookd like a mirror, and he wasnt putting in too much elbow grease. (a while ago)
Asked what he was using and it was a alloy polish called "Purple".
I went to all the car shops, etc and never found it, or they had never heard of it.
Walked into a car shop the other week (Port Kennedy for those in WA) for something and saw they had some on the shelf. I bought 6 bottles of it.
The owner tells me he has been chasing it for a while and he now eventually stocks it.
Ive got a brand new Thor replica alloy swingarm, gave it a rub with this stuff and it came up brilliant. gone over all my other alloy parts with it and same result.
Its called Purple and it is exacly that. just got to keep shaking it up whilst using it.