Shree Minerals Limited (ASX:SHH) has the drill spinning in a reverse circulation (RC) and diamond drilling campaign at the Rock Lodge prospect within its Lachlan Fold Belt Project in New South Wales.
This program will comprise 11 RC holes and three diamond holes for around 1,400 metres.
RC drilling will test Induced Polarisation (IP) chargeability anomalies and coincident gold-arsenic-bismuth soil anomalies at the northern and southern target areas at Rock Lodge.
Three angled diamond holes will target projected depth extensions to extensive base metal sulphide mineralisation discovered in historical drilling that focused on the old workings seen throughout the area in southern NSW.
Diamond drilling
Diamond holes drilled in 1985 intersected up to 8 metres of massive sulphide with recorded grades up to 4.28 g/t gold, 35 g/t silver, 0.79% copper and 13.5% zinc. One hole, SGDH08, intersected 12 metres at 1.2 g/t gold, 9.8 g/t silver and 0.2% copper.
Six RC holes were also drilled underneath old workings at Rock Lodge by Alt Resources in 2018 with this drilling intercepting massive sulphides in four holes. Results include:
- 3 metres at 2.1 g/t gold, 3.7 g/t silver and 174 g/t bismuth from 17 metres and 2 metres at 2.7 g/t gold, 11.8 g/t silver, 300 g/t bismuth and 0.48% copper from 62 metres; and
- 2 metres at 1.6 g/t gold, 9.5 g/t silver, 903 g/t bismuth from 19 metres, 1-metre at 1.4 g/t gold, 375 g/t silver, 163 g/t bismuth and 1.6% lead from 23 metres and 1-metre at 4.8 g/t gold, 0.48% lead and 1.46% zinc from 57 metres.
Shree's diamond holes will focus upon the projected down-dip extensions to this sulphide mineralisation.
RC program
Areas of old workings at Rock Lodge coincide with an IP chargeability anomaly caused by sulphide veins and quartz veins.
Rock chip samples of gossanous material and quartz veins collected by Shree returned a best result of 7.3 g/t gold with 6049ppm arsenic and 446ppm bismuth.
RC drilling will test those extensive and continuous IP anomalies that are also coincident with very anomalous soil and rock chip geochemistry.
At the southern target area, an IP chargeability anomaly is located on what is interpreted to be the southern strike extension of the mineralised trend.
Bedrock in the area is obscured by a thin layer of basaltic rock that has prevented previous rock chip and soil sampling. The target has not been drilled previously.
Prolific region
The East Lachlan Fold Belt has a long history of mineral production including gold (80 million ounces), copper (13 million tonnes), lead, zinc, silver and tin.
Regional location of Shree’s tenements within the East Lachlan Fold Belt.
It contains several large operating copper and gold mines including Evolution Mining’s Lake Cowal Gold Mine, Newcrest Mining Ltd’s giant Cadia Mine. Also within the East Lachlan Fold Belt is Alkane Resources’ 2019 Boda discovery (502 metres at 0.2% copper and 0.48 g/t gold from 211 metres).
Other targets
There are a number of other target areas within Rock Lodge EL 9155 that Shree intends to assess, including Bobundara.
Historical workings at Bobundara have a recorded production of 575 grams gold with an average grade of 21 g/t. Mining occurred during two periods from 1928-30 and 1948-49 but there has been no recorded drilling.
Shree intends to undertake additional sampling and mapping at Bobundara, including soil and rock chip sampling along strike of the main workings.
This work should lead to the identification of new drill targets, in preparation for a RC drilling program later in 2022.
IRGS models
The gold, bismuth and copper mineralisation at Rock Lodge is interpreted to have affinity with the Intrusion Related Gold System (IRGS) style of mineralisation.
There is potential at depth for bulk tonnage gold mineralisation associated with an intrusion.
The multiple veins at Rock Lodge may represent the upper zone of a mineralised system above an intrusion at depth, with bulk tonnage potential.
Planned drilling will initially target the shallow veins but pending results deeper drilling is planned to test for an interpreted source intrusion at depth.
Several Silurian and Devonian aged intrusions have been mapped in the Rock Lodge area by the NSW Geological Survey.