Make a solution of one dram of gold in aqua regia
in the usual way.
The aqua regia
method of analysis is susceptible to acid interference, which makes it unreliable if used alone.
However, further research and testing led to the development of a caustic fusion protocol, a thiosulphate leach process and, more recently, a modified fire assay method that did extract economically significant values of gold and silver as "metal-in-hand," from samples where conventional fire assay, aqua regia
leach and cyanide leach extracted very low values.
Rock grab samples from all zones, collected during 2007 ground evaluation, were submitted to Saskatchewan Research Council of Saskatoon for analysis using aqua regia
partial digestion followed by ICP.
Antimony assays were completed by GAR Aqua Regia
Digestion and Flame AA finish.
Assaying is by 30 g fire assay with AA finish for Au and further 6 elements by aqua regia
AA45 is the determination of silver by aqua regia
digestion and AAS finish.
Assaying is by 30 g fire assay with AA finish for Au and 34 elements by aqua regia
digestion and ICPES for Ag, Cu and other base metals.
A 30 gram split of each pulp fraction was then digested by 2-2-2 aqua regia
at 95 degrees for one hour, diluted to 600ml and analysed for 30 elements by ICP-MS spectrometry.
Samples were assayed at ALS Chemex Laboratories in Vancouver where the analytical procedure consists of pulverizing split samples followed by aqua regia
digestion and atomic absorption finish.