Firstly, no the core would not necessarily look like that, (it...

Firstly, no the core would not necessarily look like that, (it can do if you go through very broken ground, but usually higher up in the hole.
If it was massive sulphides, and had more time to oxidise. Then you would see a breakdown. But would not look like that.
We must remember. Core drilling is not just about getting a sample! The main objective is to be able to map the geology.
You measure the dips and angles of the structures. You look at any and every aspect, and take every reading using susceptibility, XRF, etc. Maybe every 1cm, to get every detail you can. This takes time. A diamond hole over a 1000m. You just don’t cut it up and throw it into the lab.
Core drilling cost $300+ per meter, (I’m probably out of date here!)
We all know how professional these guys are. That’s all are doing. Being professional.