Valve spring colour markings

[Gareth_C]

Hi does anybody know what the orange/green colour markings mean on a c14se valve springs
http://www.pngclub.com/forum/webkit-fake-url://35e29cb7-6b9c-41b4-9ddb-a9ed37a57925/imagejpeg

[garyc]

they sound like standard Vauxhall ones.