Bungendore Corridor

Geological setting and mineral system

Two prospects, one tenement application, on the Silurian volcano-sedimentary belt of the Captains Flat–Goulburn Synclinorial Zone, eastern Lachlan Orogen — the belt hosting the Woodlawn and Captains Flat Cu–Pb–Zn–Ag VMS deposits (R00005792). At Clare, gossans with box-work after sulphides sit at a sediment–volcanic contact with a footwall limestone in CD2; the NSW Department of Mines assessing geologist (L. A. Gilligan, 9 September 1974) characterised the lithologies as potential hosts for stratiform base-metal mineralisation of Woodlawn type (paraphrased; GS1974/404, R00024042). The synthesis holds proximal VMS as one of several live hypotheses: the prospect's own rock record — footwall limestone, pervasive carbonate alteration, pyrrhotite-dominant sulphides — is at least as consistent with a distal or carbonate-replacement setting. That Clare is “open at depth” is a conceptual inference from intersections above ~90 m true vertical — no historical hole has reached below it. At Briars, disseminated-stringer chalcopyrite–galena–sphalerite occupies a coarse fragmental pyroclastic host correlated — uncertainly — with the Captains Flat Formation (R00015205); the flat-lying working geometry is a hypothesis to be tested, not an established geometry.

The grades — what the system has already demonstrated (the only intercepts in this document)
Briars adit — GSNSW grab sampling: to 1.96 % Cu, 7.52 % Zn and 33.9 g/t Ag (R00015205, Table 2)	Independently confirmed — Geological Survey of NSW samples, independent of the operator, corroborating Teck's ten underground channels (0.42–1.14 % Cu, 0.05–1.56 % Pb, 0.29–2.50 % Zn, Ag to 25 g/t). Surface and near-surface; no tonnage established.
Clare CD1, 80.7–84 m: 2.75 m at a combined Cu–Zn tenor reported as 0.5–1 %; peak sampled values ~9,300 ppm Cu, ~9,400 ppm Zn, 7.0 g/t Ag (R00024043)	Unverified — hand-annotated sample sheet; no assay certificate sighted. The source letter reads “0.5–1% Cu and Zn”, which is ambiguous; the synthesis adopts the conservative combined reading (peaks ~0.9 % Cu and ~0.9 % Zn individually). A 0.10 m interval reported at 8 % Zn appears in the covering-letter narrative only and is down-weighted. Resolved by VW-01: sight the original certificates or re-assay the retained CD1 core (held at Londonderry, 16 boxes, 0–120 m).
Clare percussion: CP2 8–20 m — 2,940 ppm Cu, 7,650 ppm Zn, 2.9 g/t Ag; CP3 18–29 m — zone at 1.02 % Zn; CP23 14–17 m — 3,650 ppm Pb, 5,700 ppm Zn at the undrilled CD3 site (R00024042)	As recorded in the drilling-aid application; imperial-logged and converted. The 1974 sampling and analytical QA are not documented to modern standards, so these values index anomaly position pending the WP-3 re-assay of retained material.
Briars drilling — BD3, 201.85–201.90 m: 1,300 ppm Cu, 185 ppm Pb, 210 ppm Zn over a 0.05 m sampled interval (R00005792)	Best historical drill assay: confirms the Briars horizon carries base metals at depth, but was sampled over only 0.05 m — and seven sulphide-bearing intervals in the same preserved core were never assayed at all (none for gold). Phase 1 re-assays them without a rig.

Exploration history — four campaigns, three operators; every exit documented, none closed out the targets now defined
1972–74	Western Mining Corporation (EL 538 “Whiskers”)	Regional base-metal reconnaissance (stream sediments, airborne EM)	Relinquished 23 Aug 1974 on the Mining Act 1973 transition; WMC's rapid assessment recorded no significant mineralisation and it did not re-apply — yet uncontaminated streams carried high Cu–Pb–Zn, and the covered Lake George-arm plain was never effectively sampled (R00013522).
1974	Western Mining Corporation / Dampier (PLs 343/345/346 — Clare)	Stratiform base metals at the gossan corridor (Woodlawn-type per the Dept of Mines assessment)	Sulphide confirmed; no economic widths at <120 m down-hole. The proposed CD3 hole was never drilled; the PLs were relinquished and no subsequent drilling appears on the open-file record (R00024042–44).
1981–83	Teck Explorations (EL 1611 “Molonglo” — Briars)	Stratabound VMS centre west and south of the adit; soil anomalies	Volcanic-centre hypothesis recorded as disproved by the three vertical holes; relinquishment recommended. A model-driven exit: no hole was collared at the adit and drilled directly beneath it (R00005792).
2007–11	Ironbark Zinc / Cobar Management (EL 6840 “Captains Flat North”)	Verification of the Teck grid (hand-held XRF); planned ~200 m diamond hole NW of the mine	Hole not completed — land access consent not finalised within the reporting period; proximity to residences recorded as effectively precluding percussion drilling. An access-driven exit, not a geological one (R00041851).

Why the grade is still available — in the operators' own words

Wrong commodity, wrong model. Teck's own record explains why its principal survey could not see the Briars style: “No electromagnetic anomalies were found over the Briars Mine area … the pyroclastic rocks which host the mineralization are approximately horizontal in attitude, whereas the DIGHEM computer anomaly selection is based on a vertical conductor model … the sulphides are predominantly disseminated … and they include sphalerite which is a very poor conductor” (Teck Explorations 1982, R00015206, §2.3). Its three holes were then collared vertically, off the adit, against a volcanic-centre hypothesis the drilling itself disproved — a targeting-model failure, not a demonstrated absence (R00005792). At Clare the 1974 Department of Mines assessing geologist recorded both the Woodlawn-type host comparison and the counter-reading that the CD1 IP anomaly was possibly disseminated pyrite in acid volcanics (paraphrased; GS1974/404, R00024042) — a tension only petrophysics and downhole EM can resolve.

The analytical gap. Clare's historical assaying covered Cu, Pb, Zn and sporadic Ag only: gold, indium, antimony, arsenic and cadmium — the VMS payable and pathfinder suite — were never assayed; the precious- and critical-metal endowment is not yet measured (§5.4). At Briars, seven sulphide-bearing core intervals were never assayed at all, and the vein intervals never for gold (Table 6). The synthesis's re-analysis of the 2011 hand-held XRF dataset (990 readings; semi-quantitative, the synthesis's own characterisation) returned scattered Sb to ~80 ppm and As to ~40 ppm — pathfinders never measured in 1974–83 — while gold non-detection by XRF on soil is expressly not evidence of absence (R00041851).

The untested target. WMC's drilling-aid application formally proposed CD3 to test the CP23 lead–zinc intercept and coincident IP anomaly (PFE in excess of 7 % on line 53,800 N); in the synthesis's formulation, CD3 was not drilled, and this target has not yet been diamond-tested — and no hole has tested the Clare system below approximately 90 m true vertical (about 120 m down-hole). At Briars, no hole was collared at the adit and drilled directly beneath it, though the synthesis is equally clear the system is under-tested only in that narrow sense — two of three holes tested the interpreted horizon at depth, sub-economic. Cobar's own planned ~200 m diamond hole (2011) was never actioned, for access reasons (R00041851). 

The miss, precisely. No operator tested the ground and found it wanting — each missed in a way its own record documents. Teck's airborne EM was blind to a flat-lying, disseminated, sphalerite-rich style, and its three holes were collared off the adit against a volcanic-centre model the drilling itself disproved. WMC never drilled the hole its own application proposed (CD3) and never tested Clare below ~90 m true vertical. And no campaign ever assayed the elements that carry the modern case — systematic silver, gold, indium and pathfinders. What remains untested is therefore specific: the volume directly beneath the Briars adit (noting two of three holes did test the interpreted horizon at depth, sub-economic), the never-diamond-tested CD3/CP23 position, and the unassayed intervals sitting in preserved core.

System scale and the 2026 price lens

Footprint (dimensions, never tonnes). Clare: a mapped gossan of ~0.8 km inside a coincident gossan-plus-IP envelope of ~2.3 km strike, IP to ~300 m across strike — tested by four diamond holes, all ≤120 m down-hole (~90 m true vertical); part of the IP envelope may be graphitic-shale response. Briars: percent-level mineralisation along the full 50 m adit in a host flow ~15 m thick at the entrance; six soil anomalies on a 939-sample grid; a north–south low-resistivity zone of some depth extent (DIGHEM contractor); 878.6 m of core in three vertical holes.

Analogue class. Woodlawn and Captains Flat are the type analogues on the same belt, but the comparison the syntheses support is of geological character only; the Clare synthesis deliberately reproduces no analogue grade–tonnage figures, and any such parameters must be separately sourced and qualified. The conservative readings are carried as live alternatives: a distal or carbonate-replacement style with limited tonnage potential (Clare), a small fault-confined vein occurrence (Briars).

Price lens. Neither synthesis advances a commercial or price recharacterisation, and none is made here: the commercially decisive unknowns — systematic silver, gold and indium — are not yet measured, and the cheapest instrument that measures them is the Phase 1 re-assay of preserved core. Context only; no recovery, mining or processing costs applied; not attributed to any historical operator.

The targets

Primary — Clare CD3/CP23 (never diamond-tested). Its limitation, stated plainly: frequency-domain IP cannot by itself distinguish base-metal sulphide from graphitic–pyritic black shale — most IP anomalies in this belt are black shale, and the sulphide proportion of the Clare response is undiscriminated. Designed resolution: core petrophysics on retained core first, modern IP/AMT/ground-EM around the measured contrast, then CLD002 (180 m) as the first drill test, with DHEM to vector off-hole.

Primary — Briars adit undercut. BRD001 (≈250 m, angled) undercuts the only place percent-level grade is exposed. Equally plainly: the flat-lying geometry is a working hypothesis; collars exist only on a local grid, so drilling is gated on Phase 1 coordinate recovery; and Teck's reading that the adit may be footwall mineralisation underlying massive ore means any larger volume need not sit directly beneath it.

Secondary. Clare CD1 depth extension below ~90 m true vertical (CLD003, 220 m); CD2 footwall-limestone contact down-dip — the replacement/distal test (CLD004, 180 m); mid-corridor step-out (CLD005, 160 m). Briars BD3 down-plunge, shown open on the historical longitudinal section (BRD002, ≈300 m); the unassayed vein intervals in preserved core (Phase 1, no rig); and a conceptual gold target — explicitly not supported by measured gold at Briars.

Testing the thesis — gates, kill criteria, cost to answer
Briars Phase 1 — archived-core re-assay + grid recovery — A$10–18k (central ~A$14k)	Seven priority intervals in BD1/BD2A/BD3 (led by BD1 138.45–139.50 m, the inferred Anomaly A source); 4-acid ICP-MS + 50 g fire-assay Au + pathfinders; CRMs/blanks/duplicates ≈1-in-20, umpire checks; local-grid→MGA recovery. Independent of grant.	Binary, per the drill design: “if re-assay is uniformly barren (no gold, no material base-metal upgrade over the logged intervals) and coordinate control cannot be established, Phase 2 is not recommended in its current form.”
Clare verification & discrimination — <A$70k combined	VW-01: sight the CD1 certificates or re-assay the retained interval; WP-1/WP-2 georeferencing + collar resurvey (~A$25k); WP-3 re-log, multi-element re-assay (Ag, Au, In, Sb, As, Cd) and core petrophysics (A$25–40k).	If the certificates refute the hand-recorded CD1 grades, the headline reverts to the percussion-and-CD2 case; if petrophysics attributes the IP to graphite/pyrite, targets re-rank — both before any rig mobilises. <A$70k, binary.
Clare WP-4 — modern geophysics — ~A$120k	Surface IP/resistivity, ground EM and AMT designed around the WP-3 petrophysical contrast; DHEM scoped to the new holes.	Gate to drilling: discriminated, inverted targets replace the 1974 picks before holes are finalised.
Corridor drilling — conditional on ELA7069 grant, access and heritage	Clare CLD001–CLD005 (160/180/220/180/160 m; ~900 m): Phase 1 = CLD001 twin + CLD002 first CD3 test, ≈340 m, ≈A$0.15–0.25M; full ≈A$0.35–0.55M all-in, DHEM +A$25–50k. Briars BRD001 ≈250 m + BRD002 ≈300 m (≈A$255–384k; optional BRD003, A$95–140k). Full QA/QC throughout; Clare design structured for NSW co-funding candidacy.	Staged so that “expenditure is gated on geoscientific results rather than committed up front” (Briars design); at Clare, “a positive result from either materially de-risks the prospect” (Clare design). If undercut and re-assay both disappoint, the prospect “can be set down without large committed expenditure.”

Technical Manager: Dr Tim McConachy FAusIMM (1974), Senior Fellow SEG, former Rio Tinto Chief Geologist.

Data room (under NDA): technical synthesis v4.1, Phase 1 drill programme design, source register and figure set.

Contact: Doug Alcock, Managing Director, CAADIA Metals Pty Ltd — dalcock@caadiametals.com.au

No JORC (2012) Mineral Resource, Ore Reserve or Exploration Target is declared or implied. Historical results are compiled from GSNSW open-file (DIGS) records, have not been verified by a Competent Person for public reporting, and are provided for context only. The IRGS / distal-replacement interpretation is a working hypothesis under test; alternative interpretations of the geophysical data exist. Earn-in terms are indicative and non-binding, subject to contract, due diligence and grant of the Exploration Licence.