Sinclair Gold Reports 1.8Moz Mt Henry Resource, 100% Growth Update

Sinclair Gold's Mt Henry resource hits 1.8Moz at 1.2g/t Au — a 100% increase from acquisition in just six months, with 60% of the drill programme still to come.
By William Hadrian -
  • Sinclair Gold (ASX: SGC) has delivered an interim MRE of 1.8Moz at 1.2g/t Au at Mt Henry, exactly doubling the 915koz resource established at acquisition in February 2026 — with grade held steady throughout.
  • More than 70% of the 1.8Moz resource sits in the higher-confidence Measured and Indicated JORC categories, the threshold typically required to advance serious development studies.
  • The resource was generated from only 20,426m of drilling — approximately 40% of the planned 50,000m CY26 programme — with 25 holes carrying pending assays outside the current MRE footprint.
  • The resource pit-shell is priced at A$3,900/oz, roughly 40% below the spot gold price of A$6,110/oz as at 10 September 2026, providing substantial economic headroom for open-pit development.
  • A fifth rig has been mobilised and the next MRE update is targeted before the end of FY27, with both the Mt Henry and Selene deposits remaining open at depth and along strike.
Summarise with AI:

Sinclair Gold doubles Mt Henry resource to 1.8Moz in just six months

Sinclair Gold (ASX: SGC) has delivered an interim mineral resource estimate (MRE) of 1.8Moz at 1.2g/t Au at the Mt Henry Gold Project in Norseman, Western Australia, representing approximately 100% growth from the 915koz at 1.2g/t Au announced at the time of acquisition in February 2026. Crucially, grade has held steady at 1.2g/t Au throughout the doubling of contained gold. This update was generated from only 20,426m of drilling, approximately 40% of the planned 50,000m CY26 drill programme.

Q1 FY27 resource highlights at a glance

The headline figures are anchored by two large, shallow deposits, with the full resource breakdown by deposit and classification shown below.

Resource Growth & Deposit Breakdown

Key metrics at a glance:

  • Total MRE: 47.9Mt at 1.2g/t Au for 1,792koz (reported as approximately 1.8Moz)
  • Measured + Indicated: 33.9Mt at 1.2g/t Au for 1,262koz (greater than 70% in JORC M&I categories)
  • Mt Henry deposit: 22.0Mt at 1.3g/t Au for 885koz
  • Selene deposit: 24.9Mt at 1.1g/t Au for 875koz
  • Resource pit-shell: A$3,900/oz, approximately 40% below the spot price of A$6,110/oz as at 10 September 2026
  • Only 40% of the planned 50,000m drill programme has been incorporated into this MRE
  • 25 holes with assays pending outside the current MRE footprint
Deposit Classification Tonnes (Mt) Grade (g/t Au) Contained Gold (koz)
Mt Henry Indicated 12.8 1.3 521
Inferred 9.2 1.2 364
Total Mt Henry 22.0 1.3 885
Selene Indicated 20.1 1.1 710
Inferred 4.8 1.1 166
Total Selene 24.9 1.1 875
North Scotia Indicated 0.1 2.6 12
Inferred 0.0 2.4 0
Total North Scotia 0.1 2.6 12
Stockpiles Measured 0.9 0.7 20
Total Stockpiles 0.9 0.7 20
TOTAL Measured 0.9 0.7 20
Indicated 33.0 1.2 1,242
Measured + Indicated 33.9 1.2 1,262
Inferred 14.0 1.2 530
TOTAL MINERAL RESOURCE 47.9 1.2 1,792

Mineral Resources effective as at 31 July 2026. Classified in accordance with the 2012 JORC Code. Numbers may not add due to rounding.

What makes the Mt Henry resource exceptional

A Mineral Resource Estimate, or MRE, is a JORC-compliant estimate of the quantity and grade of mineralisation that has reasonable prospects for eventual economic extraction. The classification system runs from Inferred (lowest confidence, based on limited drilling) through Indicated to Measured (highest confidence, with detailed drilling data supporting the estimate).

Two things stand out in this update. First, grade has not been diluted as the resource grew. Doubling contained gold while holding grade steady at 1.2g/t Au tells you the new drilling is hitting the same quality of mineralisation, not lower-grade peripheral material. Second, more than 70% of the resource now sits in the Measured and Indicated categories, which is the level of confidence typically required to begin serious development studies.

Shallow, dense, and open — the geometry that matters

The geometry of the Mt Henry and Selene deposits is what gives the open-pit development case its strength. Approximately 90% of the gold sits within 200m of surface, and at the project’s peak depth of around 130m, the resource reaches approximately 12,500 ounces per vertical metre (oz/vm). That metric measures how densely gold is concentrated as you mine downward — higher numbers mean more gold recovered per metre of mining depth, which is directly relevant to open-pit economics.

Mineralisation at both deposits extends up to 50m thick, and Mt Henry itself is a proven open-pit producer. Historical open-pit mining operations between 2016 and 2019 recovered approximately 129koz at an average recovered grade of around 1.7g/t Au, with mining halted at approximately 90m depth. Current drilling has extended mineralisation to 480m depth, and the resource remains open in multiple directions.

A 16km corridor with significant upside

Beyond the two primary deposits, the Mt Henry Gold Project sits within a 16km mineralised corridor hosting Mt Henry, Selene, North Scotia, and a series of regional targets including Artemis, Birthday Gift, Plutus, and Apollo. It is important to note that the regional targets do not currently support JORC Mineral Resources and do not form part of the current MRE.

The source explicitly frames the broader corridor view as conceptual in nature. That said, early-stage intercepts from the regional targets are notable: Artemis has returned 12m at 6.1g/t Au and 2m at 15.8g/t Au, while Birthday Gift has returned 10m at 88.2g/t Au and 2m at 46.3g/t Au. These results indicate the broader land package warrants further exploration, though significant additional work is required before any resource can be defined at these targets.

From transaction to 1.8Moz — a six-month execution timeline

The resource growth story is also a management execution story. The company explicitly framed this update around a “what we said we would do / what we delivered” commitment.

  1. December 2025: Acquisition of Mt Henry announced
  2. February 2026: Transaction completed; maiden MRE of 915koz at 1.2g/t Au established; first rig mobilised
  3. Early March 2026: Second rig commenced mobilisation
  4. March–September 2026: Four rigs on site; mineralisation extended; workforce expanded; balance sheet strengthened
  5. September 2026: Interim MRE of 1.8Moz at 1.2g/t Au from only 20,426m drilled — approximately 40% of the planned 50,000m CY26 programme
  6. Now: Fifth rig mobilised; 25 holes with assays pending outside the updated MRE; next MRE update targeted before the end of FY27

The commitment made at the outset was to deliver meaningful resource growth before the end of CY26. The delivered outcome is approximately 100% growth in six months, with grade maintained throughout.

What comes next for Sinclair Gold

Drilling continues to grow the resource

Both deposits remain open at depth and along strike, and drilling is continuing beyond the current MRE footprint. Specifically:

  • 5 rigs are now active, focused on extensions at Mt Henry and Selene
  • Selene: 10 holes drilled outside the MRE with assays pending; the Southern Thickness Trend is currently being drilled
  • Mt Henry: 15 holes drilled outside the MRE with assays pending; deepest intersection to date at 480m
  • The next MRE update is targeted before the end of FY27

Company fundamentals

  • Cash on hand: $38.2m (at 30 June 2026)
  • Share price: $1.34 (at market close 11 September 2026)
  • Shares outstanding: 185.6M
  • Market capitalisation: approximately $249M
  • Institutional ownership: approximately 30% globally; Westgold Resources (ASX: WGX) holds 17.4%
  • Analyst coverage: Canaccord Genuity, Argonaut, Euroz Hartleys

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Frequently Asked Questions

What is the Sinclair Gold Mt Henry mineral resource estimate?

Sinclair Gold's Mt Henry Gold Project in Norseman, Western Australia, has an interim mineral resource estimate of 1.8Moz at 1.2g/t Au, comprising the Mt Henry deposit (885koz at 1.3g/t Au) and the Selene deposit (875koz at 1.1g/t Au), with more than 70% classified in the higher-confidence Measured and Indicated JORC categories.

How quickly did Sinclair Gold double its Mt Henry resource to 1.8Moz?

Sinclair Gold doubled the Mt Henry resource from 915koz to 1.8Moz in approximately six months, completing the transaction in February 2026 and delivering the interim MRE in September 2026 — using only 40% of the planned 50,000m CY26 drill programme.

What does the Mt Henry resource pit-shell gold price mean for investors?

The resource pit-shell is modelled at A$3,900/oz, which is approximately 40% below the spot gold price of A$6,110/oz as at 10 September 2026, meaning the resource was defined using a conservative price assumption that provides significant economic headroom at current gold prices.

How much cash does Sinclair Gold have and what is its market capitalisation?

As at 30 June 2026, Sinclair Gold held $38.2M in cash, with a market capitalisation of approximately $249M based on 185.6M shares outstanding at a share price of $1.34 as at 11 September 2026.

What is the next milestone for Sinclair Gold's Mt Henry project?

Sinclair Gold has five rigs active at Mt Henry and Selene, with 25 holes carrying pending assays outside the current resource footprint, and the next MRE update is targeted before the end of FY27 as drilling continues to extend both deposits at depth and along strike.

William Hadrian
By William Hadrian
Partnerships Director
William supports Discovery Alert subscribers across Australia and overseas, helping them tailor alerts, troubleshoot technical issues, and optimise platform settings to suit their workflow.
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