Hi salpetie, would appreciate your comments on this post.
I looked up RNX a couple of weeks ago and felt that the RNX magnetic anomaly and Ernest Henry were uncannily similar.
Baar, Switzerland / Sydney, Australia 17 November 2021
Glencore and Evolution Mining Limited (Evolution) have entered into a binding agreement for the sale and purchase of Glencore’s 100% interest in Ernest Henry Mining Pty Ltd, the owner of the Ernest Henry Mining (EHM) copper-gold mine in Queensland, Australia.
Glencore will receive A$1 billion, comprising A$800 million on the closing of the transaction and a further A$200 million payable 12 months after the transaction closes.
OBBSERVATION - That must mean that Glencore has very good knowledge of what the detailed geology of Ernest Henry is, being the previous owner of the mine.
Glencore is in partnership with RNX in EPM 8588, and has every reason to want this DD hole to be a success. I feel that RNX will be privy to the geological structure of Ernest Henry and would have studied it in detail when they did their comparisons. Hence their thoughts that Mongoose Deep is another potential Ernest Henry.
From : Sustainable Minerals Institute
https://smi.uq.edu.au/files/36554/Atlas_Prototype_Ch3_ErnestHenry.pdf
Description of Ernest Henry Mine
Mineralised bodies:
The main body Cu-Au mineralisation occurs ina single south-plunging shoot which in someareas has a lower grade “interlens” zone(O’Brien, 2016). A new body of mineralisation(Ernie Junior) with a similar plunge has re-cently been recognised below the main ErnestHenry mineralised body (Sullivan, 2016)
Dimensions:
The Ernest Henry orebody defines a stronglycylindrical body with a down-plunge extent ofat least 1.8km. At the northern (up-plunge)end of the orebody the shoot is approximately400m wide and 200m high. Halfway down dipit is approximately 375m wide by 175m high,and it tapers to an equal width and height ofapproximately 150m at the southern down-plunge end of the orebody. The Ernie Juniormineralised body appears to have a length ofapproximately 1200m and a maximum widthand height of approximately 200m (Sullivan,2016)
Orientation of Mineralised bodies:
The main Ernest Henry orebody is semi-cylin-drical and plunges approximately 40° directlyto the south. The Ernie Junior body appearsto have a similar orientation and lies below themain orebody (Sullivan, 2016)
OBSERVATIONS- sounds much like RNX magnetic anomaly
PORTER GEO
https://portergeo.com.au/database/mineinfo-mb.asp?mineid=mn037
ABOVE LINK IS QUITE AN INTERESTING READ
How the Ernest Henry mine was formed ( from the above link)Rusk et al. (2010) interpret the data from Ernest Henry to be consistent with the following genetic trend:
i). Rapid devolatilisation (of possibly both chloride-rich brines and CO2-rich fluids) within the source magma chamber;
ii). Fluid over-pressuring in the roof of the magma chamber as a result of volatile exsolution and vapour expansion, assisted by a seal created by magma solidification, sodic-calcic alteration and/or contact metamorphism in the carapace of the igneous complex;
iii). Possible leakage of over-pressured magmatic fluid along structures controlling the location of the later breccia pipe, producing a pre-ore potassic alteration halo;
iv). The eventual failure of the seal and sudden release of fluid pressure, resulting in a high-energy fluid flow event driving brecciation and upward transported and milled clasts. The resultant breccia mass permitted the mixing and/or subsequent ingress of basinal brines circulating within fractured rocks several kilometres above the magma chamber. Fluid mixing, rapid depressurisation and resultant cooling led to ore precipitation within the matrix porosity between breccia clasts at the top of the orebody, where, as the fluid flow, temperature and pressure declined the breccia was sealed;
v). At depth, closer to the heat source, the temperature and pressure gradient degraded more slowly, allowing for fluid-rock reaction to be more protracted, such that prolonged chemical interaction between K feldspar-rich host rocks and ore fluids led to replacement style mineralisation within clasts, with the same mineral assemblage as observed in the shallower parts of the deposit.
vi). At the deepest levels, repetition of the cycle may have resulted in the release of a new pulse of fluids which brecciated and tapped earlier formed magnetite-chalcopyrite rich rocks, telescoping mineralised clasts upwards into the orebody along narrow channels, thereby upgrading ore.
Ernest Henry mineralised brecciated K feldsparImage right - Ernest Henry brecciated hematite dusted K feldspar with chalcopyrite and magnetite veining. Polished sample. Sample collected by Richard Lilley; Image by Mike Porter, 2021.
The brecciated volcanic mass that hosts the ore forms a plunging elongate body, some 250 m thick, 300 m average length and extending at least 1000 m down plunge to the SSE. The breccia ranges from the unbrecciated volcanics, to crackle fracture veining to clast supported and matrix supported breccia to total clast digestion (massive matrix). The breccias typically contain 5-20 mm subrounded to rounded meta-volcanic and rare biotite altered meta-sedimentary clasts. The matrix is largely composed of magnetite, calcite, pyrite, biotite, chalcopyrite, K feldspar titanite and quartz. Accessory minerals include garnet, barite, molybdenite, fluorite, amphibole, apatite, monazite, arsenopyrite, a LREE fluorcarbonate, galena, cobaltite, sphalerite, scheelite, uraninite and tourmaline. The bulk of the economic mineralisation is restricted to breccia zones with more than 10% matrix.
OBSERVATION - this sounds very much like what RNX is hypothesising about their magnetic anomaly.
WIKIPEDIA
https://en.m.wikipedia.org/wiki/Ernest_Henry_mine
The Ernest Henry mine is a large copper mine located in eastern Australia, 36 km (22 mi) north-east of Cloncurry[1] in the state of Queensland. Ernest Henry represents one of the largest copper reserves in Australia and in the world having estimated reserves of 167 million tonnes of ore grading 1.1% copper and 2.67 million oz of gold.[2] Silver is also produced at the mine.[3] The mine produced 64,000 tonnes of copper and 92,000 ounces of gold in the financial year to 2021.
https://evolutionmining.com.au/ernest-henry/
OBSERVATION - The above link to article shows Ernest Henry 3D Interactive - interestingly, looks much like what RNX is thinking about their own magnetic anomaly that they are drilling. Interesting viewing.
ERNEST HENRY FACTSHEEThttps://evolutionmining.com.au/wp-content/uploads/2023/04/Ernest-Henry-fact-sheet-FY23F.pdf
OBSERVATION - this link gives a good overview and understanding of the Ernest Henry mine
All in all, I feel that RNX has a very good chance for a successful result from this DD hole. What are your thoughts on the above?
Cheers
Inky
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