New vein system discovered contains huge amounts of gold and silver per ton

Seven drill holes were all it took to kick up a stir at the Ermitaño underground mine in Sonora, Mexico. Their cores pointed to a fresh zone called Navidad, laced with gold that tests as high as 55 grams per ton and silver at more than 400 grams.

The zone sits 2,460 feet beneath the surface and 1,640 feet southwest of active stopes, yet it is still inside the royalty area watched closely by Orogen Royalties Inc. Such proximity means the find could feed the mill without costly new infrastructure.

New vein taps deeper riches

Dr. Laurence Pryer of Orogen’s exploration team says the geometry so far suggests a steeply dipping structure able to channel metal-rich fluids for hundreds of yards. “We are looking at a system with both vertical and lateral running room,” he notes.

Early intercepts show a 750-yard strike length and roughly 820 feet of down-dip continuity, and both figures could grow as four rigs punch more holes.

The main Navidad vein averages 5 feet thick, while a nearby hanging-wall structure widens to almost 20 feet in places.

Those shapes fit the textbook picture of a low-sulfidation epithermal system, a deposit style that forms less than a mile deep from fluids under 572°F. 

Why low-sulfidation veins matter

In this environment, near-neutral fluids boil as they rise, dropping quartz and precious metals into open fractures.

The resulting veins often persist for thousands of feet, and alteration halos help geologists follow them even when the ore itself is hidden.

Santa Elena and Ermitaño already sit in a well-documented swath of such veins, a sign noted in the mine’s NI 43-101 technical report.

Adding Navidad on the western flank now brackets the existing orebody between two emerging limbs.

Numbers that beat the cut-offs

Underground mines usually need at least 2.5 grams of gold per ton to turn a profit Navidad’s best hit so far logs 8.15 g/t gold over 15.7 feet, and one narrow slot spikes to 54.9 g/t.

Grades like that sit in the top quarter of global underground operations, where half of all orogenic and epithermal veins come in above 16 g/t according to a recent USGS grade-tonnage review.

Higher grades shorten haulage distances, slash power bills, and boost metal output per ton of processed rock.

Silver grades, meanwhile, reach 427 g/t, adding a valuable by-product stream.

With silver prices hovering near $29 per ounce, each ton of Navidad ore could carry more than $400 in silver credits alone. That makes bulk-mining wider portions of the vein economically attractive.

Reading the core for clues

Quartz banding, spotted calcite ghosts, and fine silver sulfide needles all show up under the core shack lights. These textures reveal multiple pulses of fluid flow, each depositing metal as pressures dropped.

Geologists also track strike length, the distance a vein runs along trend. Navidad’s 750-yard strike already rivals the 1,950-yard Santa Elena main vein farther east.

If the two link at depth, a continuous ore shoot of more than a mile becomes conceivable.

Down-hole assays list “true thickness,” meaning the width perpendicular to the vein walls. Reporting that way avoids the exaggeration that can creep into oblique drill angles and gives engineers a solid basis for mine-design models.

Royalties and ripple effects

Orogen’s 2 percent net smelter return royalty applies to every ounce extracted from the Navidad footprint.

At today’s metal prices, each ton grading 10 g/t gold and 100 g/t silver sends roughly $18 to Orogen once smelting and refining are deducted.

“Only seven holes have been completed in the Navidad vein, but the scale of the discovery is already apparent with high grade gold intercepts that are approximately 750 meters apart,” said Paddy Nicol, Orogen’s chief executive.

That comment underscores how early-stage hits can still carry big financial weight.

Investors also watch exploration success rates. Industry data show that for every hundred greenfield prospects, only one becomes a mine, yet brownfield drilling around existing operations enjoys far better odds. Navidad falls squarely in that sweet spot.

Looking ahead

Four rigs will keep twinning and stepping out through the rest of 2025, chasing both the main vein and the hanging-wall strand.

Downhole EM surveys and oriented core will refine the 3-D model, guiding production drives toward the thickest, richest zones.

Environmental work is relatively light because all development occurs under the existing Santa Elena permit block.

That allows crews to fast-track new headings, potentially blending Navidad ore with current mill feed as early as next calendar year.

Navidad’s early sting of assays hints at a system still open in every direction. If the trend holds, Sonora’s latest underground prize may soon shift from discovery headline to production schedule.

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