Ann: Exploration Update, page-40

The surface sampling won't tell us sh!t. It's completely unnecessary and the delays and trouble caused by the ASX's failures is hindering one of the most exciting projects on the ASX.

I should have posted this a long time ago, but anyway:
The microscopic fineness of the gold in the gabbro means there is no nugget effect, so the gold grade distribution at Tres Estados and Ema are represented by the bottom (gold dust) scenario in the diagram below. (from https://www.911metallurgist.com/blog/gold-nugget-effect-definition-in-sampling)



To apply this concept in a spatial sense I’ve grabbed a figure from a geostatistical article on the web. I think if the vertical and horizontal scales were multiplied by 5 or 10 they would be more applicable to the gold grades and distances we are dealing with:-

• the spatial gold grade distribution represented by the scenario on the left in the diagram below could come from an extremely nuggetty gold deposit such as Sunrise Dam in WA or the Pilbara ‘Wits’ conglomerate gold deposits;

• the spatial gold grade distribution represented by the scenario in the middle could come from a more typical nuggetty Yilgarn gold deposit; and

• the spatial gold grade distribution represented by the scenario on the right could come from a deposit with extremely low nugget with microscopic gold particle size such as what we have at Tres Estados and Ema.

If you can imagine sampling random outcrop along a traverse on the diagram on the right, then combining the samples into a bulk deposit, the average is going to be representative for the average grade of the deposit because there is no nugget effect, which wouldn’t be the case for the other more nuggetty scenarios.

Interpretation of the nugget effect: Examples of one-dimensional spatial distributions with different nugget effects and corresponding variograms:


https://www.ma.utexas.edu/users/davis/375/popecol/lec3/geostat.html