On 09/03/2014 22:57, Sacha wrote:
On 2014-03-08 17:21:43 +0000, Terry Pinnell said:

Can anyone identify these white marks on my drive paving please? I
reckon they've been visible for a few weeks.

https://dl.dropboxusercontent.com/u/...308-161824.JPG

Just a lichen of some sort. It gives new stone a pleasantly weathered
'antique' look, imo.

On virtually every paving slab round here, but can't remember the common
name