SOME ANALYTICAL ASPECTS
OF SOME GOLD PROJECT
IN INDONESIA
Rudy Obial
ABSTRACT
Results of gold determination by fire
assay method from different laboratories
are compared and discussed. Marked
discrepancies in Au analysis
particularly at low levels were noted,
The discrepancies were observed to be
due to the different sample weights
used, matrix composi-
tion and sampling error. It was found
that acceptable precision and accuracy
in fire assaying for Au and Ag at low
concentration can be obtained with at
least 50 gm sample weight ground to -200
mesh. It was also observed that analysis
of the gold prill produced by fire assay
and
determined atomic absorption is a better
procedure than straight fire assay.
Straight atomic absorption analysis of
rock and soil samples can be utilized as
a reconnaissance method of isolating
targets but not to base gold credits on.
Geological
Society of the Philippines
Unit
250, 2nd Floor, Cityland Pioneer, 128
Pioneer Street, Mandaluyong City, Philippines