I was watching this to see Erics reply. Ive seen this quite often as well, but slightly different. Ive had some that have gone brown in the centre, but kept greenery at the straggly ends of each piece of growth. They look unsightly like that, and mine eventually died completely
I didnt buy replacements for that variety.
There was a lovely specimen in my garden, inherited from my dads days. It formed a lovely dense mound of little rosettes, with pink flowers in late spring.
I'm not sure if it was a Saxifraga or a Sedum (not my field - lots of varieties to compare to, in some cases a bit siilar in appearance)
It was planted close to the edge of the driveway. It decided to explore, and crept onto the tarmac, and there it survived happily for years.
Photos to follow.
It was fairly inpenetrable by weeds for years, but I'm afraid it finally did become invaded with a fine grass. It was a major chore to pull the grass, and I was also worried in case it destroyed the tarmac, so I had to dig it all up. I split out a number of small fragments and potted them up. I planted a few pieces again. It will take a while for them to reach the proportions (about 3 ft spread) and give the effect my dad achieved.
I have Saxifraga 'Mount Nachii'
http://www.mailorderplants4me.com/products/869Its a lovely little plant - nice form, lovely foliage. Its never flowered for me though
Ive another really good one as well. Will post later