Ashford Coal Measures — Open Ground Opportunity

Ashford is the only true mining-style coal in this dataset: a mapped, discrete Permian coal-measure belt hosting NSW's historic Ashford colliery, and one of the very few workable Permian coking-coal occurrences anywhere north of the Hunter. The coal is real, shallow and outcropping — the Early Permian Ashford Coal Measures form a narrow, north-north-east-trending strip that has been drilled repeatedly since 1979 and mined historically, yet never systematically tested along its full length with a modern structural model. What makes this open ground unusual is not that the coal is unproven; it's that the coal is proven and was walked away from for reasons of scale and structural complexity, not absence.

How big is it

The scale is set by structure, not by a single seam. The controlling feature is the Severn Thrust — a major fault roughly 32 km long, along which the coal measures are preserved. Within the belt the coal measures reach up to 170 m thick in the old colliery lease, carrying two named seams (Ashford and Bonshaw). The economic unit, the Ashford seam, is a bituminous, medium-volatile, high-rank coking coal that sits just 5–76 m above basement — i.e. shallow and opencut-accessible — and ranges from 2.5 m to ~17 m thick, locally repeating to ~60 m of vertical coal where reverse faulting stacks it. In 2005 Whitehaven proved the concept by discovering the Brunt Deposit, a discrete thick-coal "pod" with opencut potential. The prize is not one pod: it's the untested strike length of a 32 km thrust that has produced one Brunt already.

Why a partner should revisit it

Every previous operator answered a different question than the one that matters now. The 1979 and 2006 campaigns drilled the belt on a regional, outcrop-following basis and correctly concluded the average coal is thin and faulted — but the same campaigns proved that where the thrust thickens the coal (Brunt), you get a mineable pod. Nobody has gone back to hunt the structurally-thickened pods deliberately, with modern structural targeting and geophysics, along the full thrust. The coking-coal rank is a premium metallurgical product that is genuinely scarce north of the Hunter, the ground is shallow, and the only coal-quality data on record is from near-surface, weathered 1979 core — meaning fresh, unweathered coal has never been properly quality-tested. It is a rare case of a de-risked geological system left open because it didn't fit a major's portfolio.

Exploration history

• Historic — Ashford Colliery (pre-modern era). Operator: colliery operators. Model: outcropping Permian coking coal on the Ashford seam. Target: coking / thermal coal. Objective: mine the seam directly. Work: underground and open-cut extraction at the Ashford Mine. Why they left: intense multiphase folding and faulting reduced the coal to a friable, non-cohesive, high-fines material; scale and structural complexity made continued mining uneconomic at the time — not exhaustion of coal.

• 1979 — White Industries Limited (White Mining). Model: follow the coal measures wherever they outcrop across the district. Target: coking coal. Objective: test the seams regionally. Work: a series of cored holes (WC-001 through WC-043+), with Ashford-seam plies sent to Coal Testing Laboratories for raw-coal analysis. Why they left: the intersected seams were "generally thin and extensively faulted" and no coal of economic potential was identified — a regional-scale verdict on an average, not on the thick pods.

• 2005–2006 — Whitehaven Coal Mining + Republic Coal (EL 6450, 6585, 6586, 6587). Model: structurally-controlled thick-coal pods along the Severn Thrust — find "Brunt-type" bodies. Target: coking coal, opencut. Objective: delineate the newly-found Brunt Deposit and hunt extensions/repeats; infill the 1979 drilling. Work: ~66 open holes in 2005–06 (which discovered the Brunt Pod); then in H2 2006, 1,970 m across EL 6450/6585 (26 Bonshaw–Olley holes), 6,275 m on Brunt including 335.7 m of cored drilling, and 1,709 m on EL 6587 — total spend $439,064 in six months. Why they left: the regional holes again hit thin, poor coal; the Olley area failed to find any Brunt extension; the recommendation was to focus only on Brunt feasibility and stop drilling the surrounding ground. Whitehaven's corporate focus was large-scale Gunnedah Basin mining — a small, structurally-complex northern pod didn't fit.

• 2006–2009 — Coalworks / Shield Energy on the adjacent Ashford Limestone (EL 6511, via Geos Mining). Model: high-purity calcium carbonate (GCC) in the Ashford Limestone belt next door. Target: limestone (Group 2), not coal. Objective: delineate bright, high-purity limestone for industrial markets. Work: 12 percussion holes in 2008, 63 samples; best 16 m @ 54.8% CaO (AFP011) and 5 m @ 55.04% CaO (AFP08); brightness 81–89% ISO. Why they left: the percussion rig was unsuited to clean sampling, an economic scoping study and diamond drilling were still required, and the licence was approaching expiry (March 2010) — work was deferred, never resumed. (Included because it shows the belt has always been explored one commodity at a time, never integrated.)

• Why the grade is still available. Not one of these campaigns was wrong — they were each answering the wrong question for this ground. The colliery proved the coking coal exists and outcrops. White Industries (1979) and Whitehaven (2006) proved the regional average is thin and faulted — and in the same breath proved (via Brunt) that the structural thickening creates mineable pods. Coalworks then diverted the district's attention to limestone entirely. So the coking coal was never mined out, never fully quality-tested at depth, and never systematically hunted along the 32 km thrust with a pods-first model. The grade is still available because the search method and the operators' scale moved on before the target was properly tested — the coal didn't.

• The miss, precisely. Every operator proved the coking coal is real and outcropping, then left — because regional drilling hit thin, faulted coal and the one thick pod they did find (Brunt) was too small for a major's book. Nobody has since gone back to hunt the fault-thickened coal pods along the 32 km Severn Thrust with a modern structural model. The coal was never the problem; the scale of the operator and the design of the search were.

Most significant grades the system has produced

Result	Best recorded value	Source	Why it matters
Ashford seam thickness	2.5–17 m clean coal; locally up to ~60 m vertical by thrust repetition	Whitehaven 2006 regional geology	Very thick for coking coal; the thrust-thickened pods are the entire prize
Coal rank / type	Bituminous, medium-volatile, high-rank coking coal	Ashford seam classification (1979 / 2006)	Premium metallurgical coal — genuinely scarce north of the Hunter
Coal-measure package	Up to 170 m thick (Ashford + Bonshaw Members)	Whitehaven 2006, old colliery lease	Substantial stratigraphy to host multiple seams and splits
Seam depth to basement	5–76 m above Carboniferous basement	Whitehaven 2006	Shallow, outcropping, open-cut-accessible
Brunt Deposit	Discrete thick-coal pod, opencut potential; 335.7 m cored in 2006	Whitehaven 2005 discovery / 2006 drilling	The one modern discovery — live proof the thrust-thickening model works
Coal quality (1979)	Best plies ~13–18% ash (e.g. WC-013 Ply 1 ≈18.4% ash; WC-041 low-ash ply ≈13.8% ash) — variable, weathered near-surface	White Industries 1979, Coal Testing Labs	Confirms clean coking-coal plies exist; quality masked by weathering — never re-tested on fresh coal
Adjacent Ashford Limestone	99.6% CaCO₃ typical; ~40 Mt @ >98% CaCO₃ historic estimate; 89% ISO brightness	Carne 1919 / Flood 1995 / Coalworks 2009	Same belt hosts one of NSW's purest limestones — a second, independent commodity

Note on quality: the only coal-quality analyses on file are 1979 samples from near-surface, partly weathered and oxidised core, which is why ash values are high and variable. High-rank coking coal is graded on coking properties, not calorific value — and those properties have never been measured on fresh, unweathered coal at depth. That gap is itself part of the opportunity.

Geological setting

The Early Permian Ashford Coal Measures form a narrow, discontinuous, north-north-east-trending outcrop belt running between the Bonshaw area in the north and the Arthur's Seat–Arrawatta area in the south. They are divided into three members: the Ashford Member (hosting the economic Ashford seam and its splits), the overlying Bonshaw Member (thin, sub-economic coal plies), and the Bukkulla Member at top. The measures rest unconformably on the Carboniferous Texas Beds to the east and are truncated on their western side by the Severn Thrust, along which Carboniferous Ashford Granite is overthrust onto the coal.

Two orogenies shaped the ground: the Kanimblan Orogeny folded the Carboniferous sediments (with granite intruded in its closing stages), and the Late Permian Hunter–Bowen Orogeny folded the Permian rocks and created the 32 km Severn Thrust and its subsidiary faults. This produced intense, multiphase deformation — dips of 20–40° NW around the old mine, steepening to 75° near Arthur's Seat — which both destroys coal fabric in places (friable, high-fines) and, critically, stacks and thickens it into pods elsewhere (Brunt). The same belt carries two further systems: the very pure Ashford Limestone (an alkali-volcanic reef metamorphosed against the Bundarra granitoids) and, adjacent, a gold–antimony vein system separately drilled next door (EL 8394; CORC0001–0008, CODD0001–0002). Ashford is best read as a multi-commodity structural corridor, not a single seam.

Top three targets

1. Brunt Deposit — extensions, down-dip and structural repeats. The proven thick-coal pod. Target its along-strike continuations and fault-bounded repeats that the 2006 regional grid was never designed to catch. Achieves: converts a known "small" opencut pod into a resource by finding the repeats the thrust should have generated — the fastest path to a JORC coal number.

2. Historic Ashford Colliery — down-dip and beneath old workings. The coking coal that built the mine is not exhausted; it was abandoned for structural and scale reasons. Test the shallow down-dip extension with fresh, unweathered core for true coking-quality analysis. Achieves: delivers the first modern metallurgical quality dataset on the seam — the single biggest data gap in the whole history — on ground already known to carry mineable coal.

3. Severn Thrust — full strike-length reconnaissance. Roughly 32 km of thrust, only patchily drilled at two ends (Bonshaw–Olley, Arthur's Seat). Use modern structural interpretation and geophysics to rank thrust-thickening sites, then scout-drill the best. Achieves: moves the play from "one pod found by luck" to a systematic pod-hunt across a corridor that has already produced Brunt once — the step-change in scale that every prior operator skipped.

Sources: EL 6585 Ashford Exploration Report 2006 (Whitehaven/Republic) · Ashford ELs December 2006 Summary (Whitehaven/Republic) · White Industries 1979 Ashford Coal (WC-holes) core logs & CTL analyses · EL 6511 Ashford Limestone Annual Report 2009 (Coalworks/Geos Mining)

Closing statement:

• Not a JORC-compliant statement; historical results reported from open-file sources and not verified by a Competent Person.

• All data sourced from publicly available NSW DIGS open-file records and public ASX disclosures.

• This article is general information only and not investment advice

• Full technical synthesis, intercept overview, drill plan and source register available on request.