Growth-focused Western Australian nickel company St George Mining (ASX: SGQ) has announced that drilling has confirmed further significant extensions of high-grade mineralisation at the Mt Alexander Project, located in the north-eastern Goldfields.
· MAD172 intersects 17.28m thick nickel-copper sulphides from 242.5m downhole:
· 242.5m to 253.5m – Ultramafic with disseminated sulphides and blebby sulphides (2mm-3mm) increasing with depth (5-10% sulphides comprising pentlandite (pn), chalcopyrite (cp) and pyrrhotite (po)
· 253.5m to 259.78m – Ultramafic with heavily disseminated sulphides and larger blebby sulphides (5mm- 65mm) (20-30% sulphides comprising pn, cp, po)
· Style of mineralisation intersected is consistent with mineralisation remobilised from a larger and proximal source of nickel-copper sulphides
· MAD172 intersected nickel-copper sulphides approximately 125m north-west and downdip of previous known mineralisation in MARC109 (which intersected 4m of disseminated sulphides)
· MAD172 establishes a substantial down-plunge extension of high-grade mineralisation with thickness and grade increasing at depth
· Downhole electromagnetic (DHEM) survey to be completed in MAD172 to search for additional mineralisation around the hole
· MAD172 was planned to test the deepest conductor drilled to date at the Cathedrals Belt, further supporting the potential for significant mineralisation in the down-dip direction of the highly mineralised Cathedrals Belt
MAD172 was completed to test the first of the seven electromagnetic (EM) conductors identified so far by the downhole EM (DHEM) surveys in the recently completed deeper stratigraphic holes along the Cathedrals Belt.
The EM plate targeted by MAD172 is modelled with conductivity of 25,000 Siemens and was predicted to be intersected at 260m downhole. MAD172 intersected thick nickel-copper sulphides from 242.5m to 259.78m downhole.
The disseminated and blebby sulphides intersected by MAD172 are consistent with mineralisation found close to massive sulphide deposits, supporting the potential for more substantial mineralisation nearby.
The high conductivity of the EM plate is not fully explained by the style of mineralisation intersected by MAD172, further suggesting potential for stronger mineralisation proximal to the hole.
A DHEM survey will be completed in MAD172 later this week, and follow-up drilling will be prioritised after review of the survey data.
John Prineas, St George Mining’s Executive Chairman, said: “Deeper drilling has already confirmed significant down-plunge extensions of the mineralised ultramafic and now – with MAD172 – we have seen the deepest intersection of nickel-copper sulphides at the Cathedrals Belt to date.
“The thickness of the mineralised intercept and the style of mineralisation support the potential for further high-grade mineralisation to be present in this area.
“Under the intrusive geological model for the Cathedrals Belt, the larger deposits of mineralisation are likely to be at deeper levels than explored to date, so it is very exciting to see the thickness of nickel-copper sulphides increasing with depth.
“We are increasingly confident that ongoing drilling could discover further significant nickel-copper sulphides down-plunge of the shallow high-grade deposits already established at the Cathedrals Belt.”