Alkane Resources Limited (ASX: ALK) has announced the discovery of significant porphyry-style gold-copper mineralisation at the Boda Prospect within its Northern Molong Porphyry Project (NMPP) in NSW.
It may be noted that Boda and Kaiser Prospects are part of NMPP which incorporates exploration licences covering an area of 110km2 of the northern MVB in the Central West of New South Wales.
The company reported that the Boda Prospect was tested with one diamond core drill hole, KSDD003, 200 metres beneath a zone of gold mineralisation previously defined in RC drilling.
ALK said that the assay results from KSDD003 indicate an increase in thickness and grade of porphyry gold-copper mineralisation at depth.
Drill intercept highlights include 502m @ 0.48g/t gold, 0.20% copper from 211 metres incl 313m @ 0.62g/t gold, 0.17% copper from 228 metres incl 12m @ 3.28g/t gold, 0.67% copper from 419 metres and 35.8m @ 0.21g/t gold, 0.49% copper from 735 metres to EOH.
Alkane reported that the assays from Kaiser Prospect confirm strong gold-copper porphyry mineralisation 200 meters southeast of the small near surface Kaiser deposit.
Significant results include 40m @ 1.30g/t gold, 0.22% copper from 0 metres incl 10m @ 2.86g/t gold, 0.36% copper from 0 metres also 2m @ 3.24g/t gold, 0.26% copper from 25 metres; and 32m @ 0.53g/t gold, 0.27% copper from 2 metres incl 11m @ 1.09g/t gold, 0.40% copper from 9 metres.
Northern Molong Belt Porphyry project
The Northern Molong Belt Porphyry gold-copper project is centred about 20km NNE of Wellington, covering an area of 110km2 of the northern Molong Volcanic Belt (MVB), in the Central West of New South Wales.
The northern MVB, within the eastern Lachlan Orogen is considered highly prospective for large porphyry gold-copper mineralisation, as demonstrated by the world class Cadia Valley porphyry district, located to the south.
The NMPP consists of three exploration licences, EL4022-Bodangora, EL6209 – Kaiser, and EL8261 – Finns Crossing.
Five complexes from NMPP exploration
Alkane reported that the exploration in the NMPP has demonstrated the margins of major intrusive complexes provide a primary control for porphyry and epithermal mineralisation.
ALK said that five discrete magnetic/intrusive complexes have been identified to date – Kaiser, Boda, Comobella, Driell Creek, and Finns Crossing within a 15km northwest trending corridor.
The company said that recent drilling targeted areas adjacent to four of these complexes – Kaiser, Boda, Comobella, and Finns Crossing (Murga Prospect) – with significant mineralisation intersected at the Boda, Kaiser, and Glen Hollow prospects.
The Kaiser-Boda target zone was mapped over a north-south strike length of 5km and 1km wide corridor defined by monzonite intrusives, extensive alteration, and widespread low grade gold-copper mineralisation.
Drilling at Boda
Gold mineralisation of 311m @ 0.28g/t Au from 19m to EOH was identified in drill hole KSRC018 in RC drilling at Boda in May 2016.
ALK said that a single diamond drill hole (KSDD003, 770.8m) was drilled to test the depth extent of the gold mineralisation identified in KSRC018 at the northern end of the Boda Intrusive Complex (BIC).
The company reported that the drill hole KSDD003 intersected a thick zone of gold-rich pyritic stringers from the top of hole vectoring down hole to a gold-rich chalcopyrite dominant core with chalcopyrite forming as disseminated blebs and in quartz veins.
ALK said that two monzonite porphyries were intersected in the first 200m downhole intruding into more primitive volcaniclastics and lavas that host the majority of the potassic alteration.
High-grade intercepts from KSDD003
The company said that KSDD003 returned significant gold-copper porphyry mineralisation intercepts of 502m @ 0.48g/t gold, 0.20% copper from 211m incl 313m @ 0.62g/t gold, 0.17% copper from 228m incl 108m @ 1.06g/t gold, 0.41% copper from 408m incl 12m @ 3.28g/t gold, 0.67% copper from 419m and 35.8m @ 0.21g/t gold, 0.49% copper from 735ms to EOH.
Drilling at Kaiser prospect
Alkane said that five RC drill holes and a single diamond drill hole for a total of 1,557 metres were drilled to test an apparent east-west trending cross structure transecting the north-south trending Kaiser mineralisation at its southern extent.
The holes were located approximately 1.5km northwest of the collar of KSDD003.
Drill results at Kaiser
Alkane reported that the drilling returned intercepts of significant porphyry style mineralisation, including 40m @ 1.30g/t gold, 0.22% copper from 0m incl 10m @ 2.86g/t gold, 0.36% copper from 0m also 2m @ 3.24g/t gold, 0.26% copper from 25m and 14m @ 0.29g/t gold, 0.41% copper from 136m incl 2m @ 0.79g/t gold, 0.98% copper from 140m; and 32m @ 0.53g/t gold, 0.27% copper from 2m incl 11m @ 1.09g/t gold, 0.40% copper from 9m.
The company said that the mineralisation is characterised by thin zones of fine disseminated chalcopyrite and bornite associated with minor silicification.
Drilling at Glen Hollow Prospect
Alkane reported that two RC drill holes for a total of 438 metres were drilled to test geochemical anomalies outboard from the Comobella Intrusive Complex (CIC) located about 7km to the northwest of Kaiser.
The company said that the drilling demonstrated the continuation of the significant porphyry mineralisation dipping to the northeast, including 42m @ 0.27g/t gold, 0.19% copper from 63m.
Updates and Future plans
ALK said that 3D modelling and further drilling is required to test the significant mineralisation positioned 200m southeast of the small porphyry style gold-copper deposit (no JORC classification) at Kaiser.
Alkane said that further drilling and an extension to the IP survey area at Boda prospect is planned to be undertaken within the licences to further define the targets.
The company reported that a detailed review of all the NMPP data is scheduled to determine geology and alteration features identified elsewhere are being integrated to develop vectors to copper-gold mineralisation, with many targets remaining to be tested in the various intrusive complexes.
Alkane’s Managing Director, Nic Earner, said: “These drill results suggest a significant and exciting discovery in a region that has a history of delivering large, low-grade and long-life gold-copper mines.
The project area has already delivered some strong indications of a big porphyry system near surface at Kaiser and, along with the results from this diamond drill hole at Boda, we can see clear evidence of Cadia-style mineralisation and grade over hundreds of metres.
Alkane is immediately prioritizing follow up drilling, seeking to determine the scale of this highly encouraging discovery”.