Well that was Saturday, goes too quick, went to Newchurch today measure for a patio, slate this one, very attractive material and hard wearing.
Slate comes in different thicknesses, as a general rule about 25mm to 30mm thick, I do not advise laying any thinner, comes in tones of grey to blue black and green.
Great for giving the area to be paved a rich, and warm feeling.
Like all natural products used for paving they attract the natural growth, but this can be washed or even brushed off without too much trouble. The colour is more stable also.
It maybe a little more money than say manmade slabs but they will last years if looked after.