If you look in your service book on the inside of the front page you will see a section called vehicle data.
On section 3 it tells you your engine code (first bold letters in section 3) and beneath that is your paint code also in bold lettering.
Once you have this if you ring your local seat garage they will be able to tell you what the exact colour is.
This information is usually in your boot also,located underneath the carpet.
Hope this helps