The Geoff (Azurite) occurrence is located at an elevation of approximately 1160 metres on a southeast-trending ridge, north of a small lake, referred to as Adrian Lake, and approximately 5.5 kilometres north of the northeast end of Tsetzi Lake. The Tam (MINFILE 093F 068) occurrence is located approximately 1.2 kilometres to the southwest.
The area is underlain by andesites, rhyolites and tuffs of the Lower to Middle Jurassic Entiako Formation (Hazelton Group). Sills and dikes of microdiorite and granodiorite related to the Upper Cretaceous Capoose Batholith intrude the Jurassic rocks.
Locally, trenching has uncovered a brecciated, quartz-carbonate–veined felsic (rhyolite?) tuff hosting traces of bornite, galena and chalcocite with malachite-azurite staining, referred to as the Geoff zone. The mineralized zone is located along the northern contact between a microdiorite sill and a rhyolite quartz feldspar porphyry. Chlorite and sericite alteration are also reported.
In 1996, a grab sample (56200) of siliceous rhyolite breccia from the area yielded 0.125 gram per tonne gold and 40.2 grams per tonne silver (Assessment Report 24710).
In 1998, sampling of a trench averaged 4.7 grams per tonne silver, 0.068 per cent copper, 0.181 per cent lead and 0.064 per cent zinc over 29.5 metres with individual samples yielding up to 33.2 grams per tonne silver, 0.36 per cent copper, 1.36 per cent lead and 0.21 per cent zinc over 1.0 metre (Assessment Report 25810).
In 2012, 22 chip samples were collected from the trench over a distance of 25 metres yielding values of up to 24.2 grams per tonne silver and 0.514 per cent copper from a select composite sample of the best mineralization (Assessment Report 33483).
Work History
The area has been explored in conjunction with the Tsacha (MINFILE 093F 055) and Tam (MINFILE 093F 068) occurrence and a complete exploration history can be found there.