Probably the guards in tile tower were watching, too. I won’t gild the lily; there are cons that swing weight in any prison, maybe four or five in a small one, maybe two or three dozen in a big one. At Shawshank I was one of those with some weight, and what I thought of Andy Dufresne would have a lot to do with how his time went. He probably knew it too, but he wasn’t kowtowing or sucking up to me, and I respected him for that.

‘Fair enough. I'll tell you what it is and why I want it. A rock-hammer looks like a miniature pickaxe — about so long.’ He held his hands about a foot apart, and that was when I first noticed how neatly kept his nails were. ‘It’s got a small sharp pick on one end and a fiat, blunt hammerhead on the other. I want it because I like rocks.’

‘Rocks,’ I said.

‘Squat down here a minute,’ he said.

I humoured him. We hunkered down on our haunches like Indians.

Andy took a handful of exercise yard dirt and began to sift it between his neat hands, so it emerged in a fine cloud. Small pebbles were left over, one or two sparkly, the rest dull and plain. One of the dull ones was quartz, but it was only dull until you’d rubbed it clean. Then it had a nice milky glow. Andy did the cleaning and then tossed it to me. I caught it and named it.

‘Quartz, sure,’ he said, ‘And look. Mica. Shale, silted granite. Here’s a piece of graded limestone, from when they cut this place out of the side of the hill.’ He tossed them away and dusted his hands. ‘I’m a rockhound. At least… I was a rockhound. In my old life. I’d like to be one again, on a limited scale.’

‘Sunday expeditions in the exercise yard?’ I asked, standing up. It was a silly idea, and yet … seeing that little piece of quartz had given my heart a funny tweak. I don’t know exactly why; just an association with the outside world, I suppose. You didn’t think of such things in terms of the yard. Quartz was something you picked out of a small, quick-running stream.