Cleaning tarnished/discoloured gas hob rings

[pls1]

The metal rings around my gas hob have become discoloured/tarnished over the years. What is the best way to clean them? Have tried a fairly aggressive oven cleaner but that turns the metal dull in colour.
Not sure what type of metal it is - looks to be a cast metal of some sort.

Untitled

• pls1
• 22 Feb 2011
• 1

 

[JohnD]

it looks like a light alloy casting (aluminium, zinc, magnesium mixture). It will probably lift off for cleaning.

a brillo pad will clean it but leave it a bit rough. A green scourer wil polish it up but will be more effort.

 

[gasbanni]

Fine wire wool. Period.