Lassedalen

4 Mt @ 24.6% CaF2 (JORC compliant)

59.622266, 9.577426

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Overview

The Lassedalen deposit is previously well explored and currently thought of as Norway's largest occurrence of fluorspar. There has been drilled 28 holes in the location and the deposit is still open to continuation in depth and length. Mineral Holding AS are currently acquiring and analyzing the project to identify if it could still be viable today. In 2012 a JORC compliant resource estimate along with a positive economical scoping study was completed.

Highlights

General

Fluorspar is an EU critical mineral, last stated in the 2023 list.

Lassedalen

The 2012 preliminary economical assessment resulted in a Pre-Tax NPV of 31.6 m$USD at a 10% discount rate, with a corresponding Pre-Tax IRR of 20.2%. However current Fluorspar prices might be lower.

The JORC-compliant resource estimate identified 4 Mt of high-quality acid-grade fluorspar at 24.6% CaF₂.
Any increase in mineable ore, either through resource expansion, improved conversion to reserves, or deeper drilling, can significantly enhance the project’s overall expected economic performance.
Close proximity to Mineral Holding AS' Kisgruva deposit, possibly allowing for capex-sharing between different projects with joint tailings, facility, staff and equipment.

Geological Setting

The Lassedalen deposit formed along an east-west striking, south-dipping fault zone of Permian age that cuts through Mesoproterozoic volcanic-derived gneisses of the Kongsberg Complex. It was developed during regional extensional tectonics, where the ~4.5 km long fault zone is characterized by crushing and brecciation of the host rock, forming a hydrothermal breccia system. This deformation created a network of fractures and cavities for the circulation of warm, CO₂-bearing saline fluids enriched in fluorine, silicon and calcium. The mineralization occurred as these fluids precipitated minerals within the open spaces of the brecciated gneiss.

Location and infrastructure

Lassedalen is located in Saggrenda west of Kongsberg in eastern Norway. The deposit extends for roughly 4.5 kilometer predominantly underground.

Its location is highly advantageous. Kongsberg, with a population of about 29,000, offers well-developed infrastructure and access to an experienced local workforce. The E134 highway crosses the eastern end of the deposit, providing excellent transport and logistics. The area also benefits from reliable power and water supplies.

Mineralogy and Metallurgy

The deposit consists predominantly of coarse-grained, typically white fluorspar/fluorite accompanied by quartz and calcite as gangue minerals. Minor disseminated pyrite and iron-poor sphalerite are locally present. The relatively coarse grain size and breccia hosted nature of the fluorspar suggest favorable liberation characteristics. The metallurgy of this deposit type tend to be generally conventional for crushing, grinding and flotation to produce an acid-grade fluorspar concentrate, which was tested with positive results. The previous testwork at Lassedalen produced a high-quality high-purity fluorspar (97%+ CaF2, <1% SiO, <1% CaCO3) with 28 separate flotation tests accounting for variations between samples.

Conducted and future work

Mineral Holding AS is currently relogging and reviewing data from the previous project holder to obtain a better understanding of the economic potential. However, market research show that even though fluorspar is an EU critical mineral, the current European fluorspar prices appear to be relatively low, making the viability of the project uncertain. This low price is likely caused by imports from low-cost foreign producers, which is why Mineral Holding will slowly advancing this project cautiously and at low cost.