Joe,
have you just scratched it by polishing it (with grit in the cloth or something), or have you just discovered the scratches? - your post is a little unclear...
If it's the latter, look in Yellow Pages for a firm called 'Chips Away'. They are a locally franchised business which specialise in re-touching stone chips in paintwork. They did an excellent job on my next-door neighbour's (metallic) people carrier - will come to your house or place of work and are not expensive...
Kev
ps Gloss black will be a piece of old ease to fix, too....
This is easy.