Actually, they can and have reported the presence of massive sulphides in the core prior to receiving assay results. The presence of pyrite, galena(lead) and sphalerite(zinc) is obvious as soon as it's removed from the core barrel and companies are allowed to report visibly massive sulphides. The discovery hole, SJ18-21, is a vertical hole so it doesn't appear it was primarily intended to help map out the steeply dipping veins. They are also trying to find the source of the mineralization at depth. The presence of the denser mineralization may indicate they are getting close so it will be interesting to see how far they are prepared to drill. Perhaps if they intersect the intrusives postulated to lie below then they'll stop. It's risky but a good exploration shot based on the results to date.