Red's probably right Mrs What. It's probably unusable. I think it would be very small as well........... without any straight and polished edges. Best to buy an off-cut.
For draining board............. you know about the grooves cut into the granite.........
A possibility ........... a few years ago when Belfast "Butler" sinks were the big thing, I bought a matching draining board (same manufacturer, same material) and sat it on the worktop so that it drained into the sink.
It had a lip around the edge so that you could dump wet clothes etc without water getting onto the worktop.
Could do something like that in granite, but I bet it would cost though. :o)