Craig, from what I can see in the photo, I would go with sedimentary. The particles appear to be quite mixed in size and it looks like the rock broke around particles and not through them (although a real close-up would help determine that). There is a slight indication of what could be foliation at the top, but I think it is an artifact.
Thanks for your reply Donald, The rock does react with hydrochloric acid, There looks to be some grain break opposite of the planar cleavage surfaces and are shiny spots through the break of the rock. Would that indicate a marble or would it be limestone ?
Hi, The rock might be a calcite cemented clastic sedimentary rock, such as sandstone. I'd try scratching a piece of glass with it. It it scratches glass, it's probably calcite cemented sandstone. It might also be a calcarenite--essentially a calcite sandstone. In either case, it looks sedimentary to me.