Hey $b_rich$, you'll love this! I made a math error on the Lewis hibar results (4 samples) - they actually average 0.014 oz/yard. So, just over half of the average used by all of the GDSM/WSRA/Gold Tech reports which was 0.025 oz/yard. I apologize on this public forum - as much as it pains me, I am willing to admit I erred. How often do you see apologies on IHub?
However, it doesn't change much. The Lewis report is still only 15 samples to characterize many millions of tons of gravel, and has no description of how the samples were collected and processed. The old Southwestern report (1964) still has no assays, and that was where the 0.025 oz/yard estimate came from.
Maybe GDSM can provide the Lewis report and everyone can whip themselves into a frenzy making the conversions themselves, for what it's worth.
