Lilac is quite a complicated variety that takes a lot of selective breeding to get the right tone to the colour. It’s not unusual to see lilacs with an overall blue tone rather than the dove pink that’s required.

What American rat clubs call lilac is an entirely different colour genetically, with an entirely different standard to the UK lilac.

Genetics: British blue, chocolate, sometimes mink – or carrying mink – plus one copy of the red eye dilute gene (aabbddRr, sometimes with mm or Mm)

NFRS Standard: To be a warm pinky grey. Faint light speckling or a subtle ticked effect (heathering) is usual for this variety and is not a fault. Colour to be level throughout. Not to be confused with platinum or lilac. Belly colour to match top, undercolour pale grey to the skin. Eyes Black.