h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I recall a paperback book I had as a teenager (late 1960s), probably classed as SF. The cover was a man's face, immensely lined as though made of layers of paper. The story featured someone who was very long lived & I have a feeling stone or white came into the title or author's name.
very little to go on, but I wonder if anyone can suggest what it might have been

Family Stone by Robert Heinlein?

Yeah, my guess was Heinlein's recurring character Lazarus Long.

I should reread all my Heinlein books. I bought every Heinlein book I could get my hands on when I was a teenager. I think I managed to get almost every story he wrote. Many of the paperbacks I bought sat too long in the book case at the head of my waterbed and stuck together, but I think they're still mostly readable... maybe. It's an impressive but worthless collection.

Could this be the book cover you're thinking of?

http://www.parigibooks.com/pictures/6986.jpg

Alas no, it wasn't as well known as Heinlein. I think it involved children & a cave - very vague, I'm afraid.

Children and a cave would always bring John Saul to mind - but his writing was more of a horror fiction than sci-fi.

The sword in the stone, by T H White?

Merlin's face on the cover looks lined
http://www.amazon.com/Sword-Stone-Terence-Hanbury-White/dp/0399225021

Nothing as well known as that. The copy I had, was bluish & the face took up most of the picture. I've a feeling it was a cave on an island - perhaps not so much SF as an odd story.

Ah well, I'm not yet "old". In the 60's, I was sneaking off with my eldest brother's 1st edition Marvel comics and some Asimov, Clarke and the like.

I used to think 60 was old. Now that I'm 70, I think 90 is old. My father, who is 98, may have other ideas.

Weirdstone of Brisingamen?

Not that either. But thanks for the suggestion.
I think I've found it, 'The Master' by T H White.