Re: Antimony and Arsenic: NOT A VALID CONCERN...
posted on
Oct 24, 2009 02:29PM
Beware of CONTINUED mis-representing of facts by focusing on select information ("...have seen in the report that some drillholes containing 1% (10,000 ppm) and some with 2240 ppm...", statements which do not represent the proper context of the information as fully presented in the report! Most of the Silverado antimony is, for all intents and purposes, arsenic free. The full market value of most of Silverado's antimony will be fully realized with minimum processing, far less that the 50% $$ loss alluded to (stated?). The following is from the SAME Silverado pre-feas report (emphasis mine), and remember, almost all of the assays are showing far more that 10% Sb, in fact, the average is now 50% Sb!!:
"For 159 or 87 percent of the analyses, arsenic levels average 2,240 ppm (0.224 percent) and lead values are very low, averaging just 19.7 ppm. The highest lead value was 275 ppm, indicating that lead only exists in very small amounts in the mineralized rock. However, for 15 or 8 percent of the mineralized intercepts, arsenic values are >1.00 percent. Arsenic levels in zones of >10 percent antimony average about 0.18 percent. The maximum arsenic value for these higher grade Sb intervals (n=55) is 0.31 percent (#203789; Appendix I). During development of milling technologies, Silverado’s work will focus on the most effective removal of arsenopyrite from the stibnite concentrate prior to marketing. This is discussed further in Chapter 18.3 ofthis Technical Report. The metallurgical data shown by the Hazen Research on the Bulk Sample (see figure16.1) shows that arsenopyrite and gold report to separate mill circuits during gravity processing. The QP reviewed tin, bismuth, selenium, and tellurium values. For the majority of the mineralized zones, values were below limits of detection as indicated in Table 16.2, indicating that they do not constitute a significant metallurgical contaminate. Jimminy Christmas.