Carex morrowii ‘Ice Dance’ maybe? The edges look to have ice on them!
http://bertcuijpers.nl/shop/ca...
http://www.growsonyou.com/spri...
http://www.wavecrestnursery.co...
I found a photo showing flowers but it's not the best ..
Densely tufted grass with arching narrow variegated leaves of deep green and white with an usual twist at the tips
http://www.jacksonsnurseries.c...
The tips of the leaves on the plant in question look to have been cut off.
If the white stuff on the edges does happen to be ice, it looks like Carex laxiculmis 'Bunny Blue' ..
http://www.mypalmshop.com/CARE...
