Do we have any mining/geo types who know why they need the...

Do we have any mining/geo types who know why they need the presumably more expensive diamond drilling for under the pit? Would have thought any gold they find down there is good gold, so RC would be fine...no need for much geochem analysis...

I have basic knowledge such as this, but don't see a ready answer. http://www.locosistemas.com/2015/04/22/advantages-and-disadvantages-of-diamond-core-drilling/

Maybe they are drilling from slightly unstable areas, so it's just a safety issue? Set the rig up and walk off.