Report on Pighole Area EL1473 and EL2150

Abstract

The present work has focused on the sulphidic, cherty siltstone units which have been partly mapped and chip sampled, although the quartz reefs and veins have also been given some attention. The mapping was based on 1:16,000, Commonwealth aerial photography flown in 1963, and 1:4000 enlargements of the same. The gold results are disappointing, the significant values being largely confined to samples taken from or adjacent to old prospecting pits at Annie Oakley, Beef Bucket, Dolly Pot and Sweat Ridge. The best result of 47 ppm over 42 cm comes from Beef Bucket. However, this and other significant results should be viewed in the light of (i) the thinness and limited strike extent of the mineralized unit, and (ii) the high arsenic content (0.1 to 0.4 %). Gold and arsenic contents in general have a good correlation (coefficient = 0.85), indicative of a gold-arsenopyrite association in the primary zone. The mean arsenic content of all samples taken is 404 ppm. There is little correlation between sulphide volume and gold content in the case of the sulphidic siltstone units.