Well that's a very good question. What's interesting is the...

Well that's a very good question.
What's interesting is the ground where these nuggets were found and I think it would do investors well, to revisit some of the recent map overlays for reference. Included below for easy ref as well as some google screenshots.

The maps can be a little confusing. And I think there is a common misconception that the Bellary lies above the mt Roe. The maps show Bellary dome at the centre of the tenement, surrounded by Mt Roe and it appears to be, as per its name, a dome. It is, in fact, more akin to a depression/crater.
The trap site (approx) is a perfect place for nuggets from the Mt Roe/Conglomerate horizon (eroded over time) to reside. There are likely other areas of concentrated nuggets left from the disintegration of the conglomerate underlying the Mt Roe basalt, which is long gone. On the maps, you can also see the Archaen basement, this is the end of the stratigraphic line for gold. The layers would be in sequence from bottom to top: Archaen basement-Bellary formation-Conglomerate horizon-Mt Roe basalt.

So what is exciting is the fact that if gold is determined to be from a conglomerate below the Mt Roe, then all the surrounding Mt Roe basalt could potentially contain a lot of gold.

Where gold is found spilling OUT from the conglomerate at the edge of Mt Roe in the north-west, at this particular formation, it appears to be spilling IN towards the "dome" centre, residing in trap sites. The gold may have originated from an extension of a stratum which lies below the surrounding Mt Roe.
If that is the case, there could well be an extensive layer of nugget gold.

The BIG question is whether there exists/existed a layer separate from the nugget laden conglomerate, which contains fine gold as evidenced in the panned samples.