Western Australian gold exploration and development company Excelsior Gold has announced the commencement of drilling at the historic Zoroastrian underground mine which will be funded by cash flow generated from the company’s current open pit mining operations.
The company said the three hole initial reverse circulation (RC) drilling program at the northern end of the Zoroastrian Extended pit is testing for depth and strike extensions to the high grade gold mineralisation mined in the original Zoroastrian underground workings in the early 1900s.
The historic Zoroastrian underground mine was developed to a vertical depth of 100 metres at the beginning of the 20th century and produced approximately 56,000 ounces of gold. The underground mine was focused on a persistent narrow (0.3 to 2 metre, average 0.6 metre wide) quartz vein called the Main Lode within the Zoroastrian Dolerite.
Excelsior said historic mining records describe the vein as “extremely rich” patches of “specimen gold” with the highest recorded assay of 2,551g/t Au (82oz/tonne).
According to the company, historical drilling at the northern end of the pit returned assay grades of 8,522g/t Au (274oz/tonne) over 2 metres downhole and 560g/t Au (18oz/tonne) over 3 metres downhole.
“Excelsior Gold has recently conducted a detailed program assessing the historic underground sampling data to facilitate three dimensional modelling of the high grade zones,” the company said in a statement to the ASX.
“Through this program the Company has discovered the historical records include average drive sample intervals of: 1 Level 134 metres @ 15.4g/t Au; 2 Level 162 metres @ 50.4g/t Au; 3 Level 88 metres @ 23.6g/t Au; 4 Level 62 metres @ 8.0g/t Au.”
The current three hole drilling program will be completed by the end of March.