Help needed removing spilled plaster from patio!

[markthedoc]

I've recently had my front room plastered.
However the plasterer made a right mess of my patio with spilt plaster.
What is the best way of getting rid of this?
I've tried chiseling most of it away but theres still some left.
Many thanks

 

[masona]

Try this www.bilbotools.com/acatalog/Cleaning_and_Treatement_Products.html

 

[DAZB]

Pressure Washer at close range will shift it.