Related Clues:

• A mountain lake is hard to discolour
• Trains ridiculously hard — it's not looking good for cup
• Stain bottom of post with gloss, not top
• Like mere soil?
• Film seen by a sailor mid-evening is hot!
• It's black on a silver background
• A shirt spoilt - hide new stain
• Discolour
• A dull film the couch potato doesn't mind watching
• Go dull like small lake in the mountains
• Discoloration caused by swirling rains in the centre of Eltham
• Become dull
• Corrode coating with time replacing top
• Take the shine off
• Sully's unopened lacquer on view next to last vestige of paint