By Charles Pitts
Meridian Mining UK.S (TSX: MNO) has confirmed a significant expansion of its mineralized footprint in Mato Grosso, Brazil, reporting the discovery of a second high-grade Volcanogenic Massive Sulphide (VMS) layer at its Santa Helena project. The announcement, highlighted by the first instance of visible gold observed in the Santa Helena area, suggests that the project may host a more complex, stacked mineral system than previously modeled.
The discovery comes just months after the company declared a maiden resource for the Santa Helena Central zone. Drilling results from hole CD-869 have intercepted a multi-metal horizon located below and to the east of the known resource, returning high-grade gold, silver, and zinc. This development aligns with the geological profile of the Cabaçal VMS belt, where mineralization is often found in multiple, successive layers: a characteristic that could significantly increase the overall tonnage and metal content of the Cabaçal hub.
New VMS Layer and Visible Gold Intercepts
The technical centerpiece of the recent campaign is hole CD-869, which targeted a down-dip extension of the Santa Helena North IP (Induced Polarization) anomaly. The hole returned 7.2 meters grading 1.4 g/t gold, 24.3 g/t silver, 2.3% zinc, 0.9% lead, and 0.1% copper. Critically, geologists logged visible gold within the sulphide zone of this interval, a first for the project.
According to Meridian’s technical team, the presence of visible gold at Santa Helena points to two primary geological possibilities: a structural gold overprint: where later geological events deposited gold into the existing VMS structure: or a gold-enriched VMS style. The latter would mirror the characteristics of the nearby Cabaçal deposit, which served as a major copper-gold producer for BP Minerals and Rio Tinto in the late 20th century.
Additional drilling in the area has reinforced this gold-rich trend. Hole CD-859, located approximately 390 meters west-northwest of historical drilling, intersected 0.8 meters grading 5.0 g/t gold and 1.0% zinc from a shallow depth of 63.2 meters. These results indicate that the gold mineralization is not isolated to a single “sweet spot” but is part of a broader, emerging trend that remains open in multiple directions.
Strategic Importance of the Cabaçal Hub
For operators and investors, the Santa Helena discovery is a critical component of Meridian’s “hub-and-spoke” strategy. The project is situated roughly 10 kilometers southeast of the Cabaçal mine, the primary asset in the company’s portfolio. By identifying multiple satellite deposits within trucking distance of a potential central processing facility, Meridian aims to maximize the scale and economic viability of the entire VMS belt.
In January 2026, Meridian declared a maiden Measured & Indicated (M&I) resource at Santa Helena Central of 5.3 million tonnes (Mt) grading 0.6 g/t gold, 0.4% copper, 15.5 g/t silver, 1.9% zinc, and 0.4% lead. This resource was defined as open-pittable and remains open for expansion. The discovery of a second layer beneath the existing resource suggests that the vertical potential of the site has been underestimated.
The broader Cabaçal VMS belt now represents one of the more significant emerging base and precious metal districts in South America. Current M&I resources across the belt are estimated at approximately 1.4 million ounces of gold, 0.6 billion pounds of copper, and between 5 and 6 million ounces of silver, in addition to substantial zinc and lead credits.
Market Snapshot: June 2026 Commodity Trends
As Meridian moves toward feasibility studies, the price environment for its primary metals: copper and zinc: remains a focal point for market analysts. Zinc, in particular, is seeing renewed interest due to its role in galvanized steel and emerging battery technologies.
| Commodity | Spot Price (Approx.) | 24h Change | 2026 YTD Trend |
|---|---|---|---|
| Gold | $2,345 /oz | +0.4% | Bullish |
| Copper | $4.65 /lb | -0.2% | Consolidation |
| Zinc | $2,980 /t | +1.1% | Bullish |
| Silver | $29.10 /oz | +0.1% | Stable |
The copper supply forecast for 2026 continues to be driven by the energy transition and the expansion of AI data centers. Meridian’s ability to deliver a multi-metal product could provide a natural hedge against volatility in any single commodity market.
Metallurgy and Recovery Success
One of the primary risks in multi-metal VMS deposits is the complexity of mineral processing. Separating gold, copper, zinc, lead, and silver into marketable concentrates can be technically challenging and capital-intensive. However, initial metallurgical testwork for Santa Helena has yielded favorable results, suggesting the project could produce clean, high-grade concentrates with high recovery rates.
Fresh rock samples from Santa Helena Central demonstrated recoveries of approximately 90.6% for zinc, 76.9% for copper, 78.3% for lead, and 57.0% for gold. The relatively high silver recovery of 83.7% adds significant “sweetener” value to the base metal concentrates. These figures are essential for the project’s economics, as they indicate that standard flotation methods: the industry norm for VMS ores: will likely be effective.
The company is currently optimizing these recovery circuits to improve gold capture, particularly focusing on the recently discovered visible gold. If a significant portion of the gold is “free-milling,” it could potentially be recovered through gravity circuits, further lowering operating costs.
Geopolitical Context: Brazil as a Mining Destination
Brazil continues to solidify its reputation as a stable jurisdiction for critical minerals and base metals. The Agência Nacional de Mineração (ANM) has been working to streamline permitting processes, though environmental regulations remain stringent, particularly in states like Mato Grosso.
Meridian’s operations benefit from established infrastructure. The Cabaçal region is characterized by flat-to-rolling terrain with good road access and proximity to existing power grids. Unlike high-altitude Andean projects or remote Arctic mines, the logistical burden at Santa Helena is relatively low. This infrastructure advantage is a key factor in the project’s timeline, potentially shortening the path from discovery to production.
Timeline and Key Risks
The discovery of a second mineralized layer necessitates a re-evaluation of the drilling schedule. Meridian has indicated that it will continue to prioritize “step-out” drilling to define the limits of this new zone while simultaneously infilling the Santa Helena Central resource.
Key Milestones:
- H2 2026: Continued diamond drilling focusing on the depth extensions of the Santa Helena North IP anomaly.
- Q4 2026: Updated metallurgical results incorporating high-grade intercepts from the second layer.
- 2027: Integrated Pre-Feasibility Study (PFS) for the Cabaçal Hub, combining the Cabaçal and Santa Helena resources.
Key Risks:
- Geological Continuity: While the “stacked” VMS model is common, the continuity of high-grade pockets between drill holes is not guaranteed. Further infill drilling is required to confirm resource reliability.
- Permitting: Mato Grosso has specific environmental requirements regarding water usage and tailings management. Any delays in the Environmental Impact Assessment (EIA) could push back the production timeline.
- Capital Markets: Despite strong commodity prices, the cost of capital for junior and mid-tier miners remains elevated. Meridian will need to secure significant project financing to move into the construction phase.
Outlook for the Cabaçal VMS Belt
The identification of a second mineralized layer and the presence of visible gold significantly de-risk the exploration thesis for Santa Helena. It confirms that the project is not a simple, single-lens deposit but part of a larger, more robust geological system. As Meridian Mining continues to expand the Cabaçal hub, the project is positioning itself as a central player in Brazil’s burgeoning critical minerals sector.
For the global mining industry, Santa Helena serves as a reminder that well-explored brownfield districts still hold the potential for world-class discoveries. The combination of high-grade base metals and precious metal “sweeteners” makes Santa Helena a project to watch as the 2026 exploration season progresses.
Could this discovery change the mining landscape in Brazil? Seems like there’s a lot of potential here.