Correct tool to cut concrete edging?

I need to cut 3 pieces of flattop edging but don't have the appropriate tool - is an angle grinder the right tool? Bit confused by the blades if it is - I see stone blades, but they look very wide, is diamond the right type?

Anyone able to point me in the right direction?

The edging is the 50mm wide stuff like http://www.buildershoponline.co.uk/...0_x_915mm_Flat_Top_Edging_LP003_0-500x500.jpg

Thank you!

A 9" angle grinder will do it, a stihl saw would be better.
You want a stone cutting blade/disc rather than a grinding blade/disc. The grinding discs are much thicker.
For 3 cuts, you would be better of hiring an angle grinder, rather than buying it. No need to go to the expense of diamond tips for 3 cuts either.

Brilliant, thank you for the advice