Three Rare Earth Projects That Might Be Flying Below Your Radar (Part 3 of 3)

Sep. 5, 2013

In this three-part series we cover three of the world’s lesser-known rare earth projects. While it is easy to get caught up in the horse-race of projects owned by publicly-traded juniors, it’s important to acknowledge the array of less-conventional, yet still promising, rare-earth projects that are riding below the radar of many. With juniors facing an ensuing drought for capital, and equity markets still fluttering on broader economic woes, private- and sovereign-backed projects may enjoy a strategic advantage as the shakeout of the rare earth industry escalates.

Part 3: ecoNatura’s Mulas Rare Earth Project in Spain

The Mulas Rare Earth Project, located in central Spain, is owned by ecoNatura, a private consultancy based in Madrid, Spain. Mulas is a placer deposit, comprised of unconsolidated sandy and clayey alluvium. The alluvium hosts relatively large-sized (0.3 to 1.25 mm) monazite nodules that are comprised of roughly 60% TREO by weight, according to a project summary report from the company.

In 1990, the Russian Institute of Mineralogy, Geochemistry, and Crystal Chemistry of Rare Elements (IMGRE) conducted research on a pilot area of the deposit containing 2.9 million m3 of alluvium. The study concluded that the pilot area contains 1.8 kg of monazite per m3, equating to 5,220 tonnes of monazite in-situ. Follow-up research in 1991 examined sediments to the North and West of the pilot area. A total of 467 small pits (up to 5 meters deep) were excavated within an area covering approximately 10 km by 2 km. The study inferred that an additional 21.2 million m3 of sediment contained 1.98 kg of monazite per m3 of alluvium, equating to an additional 42,000 tonnes of monazite in-situ.

Historic research suggests presence of a 48 million tonne deposit

Although a JORC or NI 43-101 compliant resource or reserve estimate has not been completed for the Mulas deposit to date, ecoNatura told us that the historic research on the property conservatively suggests the presence of a 12 million tonne deposit grading 0.175% TREO, along with an adjacent 36.0 million tonne deposit, grading 0.110% TREO. Collectively, this estimate suggests that the Mulas deposit may host around 60,000 tonnes of in-situ TREO, which is comparable to that of the Hoidas Lake, Clay-Howells, and La Paz projects.

The company had three samples analyzed by ALS Minerals Laboratory Group in 2013, revealing an average relative distribution of REOs as follows:

  • 95% La2O3
  • 93% CeO2
  • 77% Pr8O11
  • 26% Nd2O3
  • 18% Sm2O3
  • 40% Eu2O3
  • 78% Gd2O3
  • 21% Tb4O7
  • 40% Dy2O3
  • 38% Ho2O3
  • 03% Er2O3
  • 05% Tm2O3
  • 06% Yb2O3
  • 00% Lu2O3
  • 60% Y2O3

Exceptionally high abundance of Nd, Pr, and Dy oxides for a monazite deposit

Compared to a Mt. Weld monazite, the samples from Mulas contain an exceptionally high relative abundance of Nd, Dy, and Pr oxides.  Using the relative distribution of REOs from the Mulas samples above, the basket price is $47.79/kg versus $34.18/kg for the Mt. Weld CLD, based on March 26, 2013 FOB China prices for separated REOs from Metal-Pages.

From extensive sampling of the deposit, the company has identified several zones with elevated concentrations of monazite. By selectively mining the richer areas of the deposit only (areas containing no less than 3.66 kg of monazite per m3) ecoNatura believes that an operation can yield upwards of 23,000 tonnes of monazite.

Additionally, based on studies conducted in 1991 in collaboration with IMGRE, ecoNatura revealed that desliming, screening, gravimetric concentration, and magnetic separation can yield a 95% pure monazite concentrate (approximately 55% TREO by weight) from the Mulas ores for the impressively low cost of $7 per tonne of ore processed. Assuming an 80% recovery rate during concentration, this equates to an operating cost of approximately $5,000 per tonne of TREO contained in the monazite concentrate product – far lower than the $35,400 per tonne average of the world’s 23 development-stage rare-earth projects (see recent report from Adamas Intelligence). Phosphate, rutile, and zircon are all potential by-products at Mulas, although none have been economically proposed or investigated to date.

Currently, exploration is underway on the Southern extent of the alluvial deposit. Collectively, ecoNatura is planning to excavate and sample a total of 1000 pits; 500 from previously untested alluvium, and 500 from historically-sampled areas in order to confirm the resource estimates put forward in the early-90s. Coinciding with this exploration and definition work, the company plans to conduct geophysical analyses and define a NI 43-101 compliant mineral resource. It also plans to have tests conducted in Germany to assess the prospect of separating high-purity REOs from the Mulas monazite nodules.

Advancing with three aces in its sleeve

Although it’s early-stage, the Mulas project is advancing with three aces in its sleeve. First, the deposit’s purportedly-high relative abundance of desirable Nd, Dy, and Pr oxides offers the project an uncharacteristically-high basket price versus other LREO-rich deposits globally. Second, the deposit’s geographic proximity to Rhodia’s LaRochelle REO separation facility in France can serve as a major benefit should the company decide not to separate its own REOs. Third, the deposit’s relatively low concentrations of Th and U (collectively around 0.2 weight % of monazite) should alleviate social and environmental concerns related to development of the deposit, helping streamline its path to production.


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