Gillian, I think you may know the answer to this

[Gillian Harvey]

Well I know the fur on my blue point Ben (who actually looks blue grey (LOL!) overall ) is much lighter at the base of the hair - and their is a distinct 'line' where the light and darker hair meet. Funny that she thinks its a recent thing though 

[Rosella moggy]

If your friend hadn't have said it was recent then I would have said he could be a black smoke. However, could it be dead fur and just that his undercoat needs a thorough defluff?  Is the shaft of the hair partway black/grey? 

I'll pass on your comments, thanks. Sorry dumb I am, er what exactly is the shaft of the hair?  I got the impression that this is not a gradual change of colour but a distinct change after about 1/2 inch from his skin from a rather nice grey to "black" (or such a dark brown that it looks black altho has a brown tinge to it if he spends time in the sun).

[candyshandy]

If your friend hadn't have said it was recent then I would have said he could be a black smoke.

However, could it be dead fur and just that his undercoat needs a thorough defluff?

Is the shaft of the hair partway black/grey?

[Rosella moggy]

Gillian (or anyone else of course) but thought Gillian might know due to Persians and grooming experience.

A friend of mine has 4 Persians, one of which she says is not a "true" persian but looks very much like one. He is black and white and his name is Guinness. He is 7 years old this week

My friend grooms him regularly. His fur is about 3 inches long. She has just noticed that the first 1/2 inch or so of his black fur has recently gone a beautiful shade of grey. It looks a bit like the roots of a person who badly needs to re dye their hair .  Have you ever come across this? 

No idea if it might be related but Guinness had to be shaved (poor lad) many years ago when he was very young due to ringworm. My friend is however absolutely sure this colour change is a recent thing.