Norway is rich in natural resources and Vevring/Engebo contains one of the largest massive deposits of eclogite, a rock that by some is referred to as Norway’s national rock. The deposit feature high grades of garnet, clinopyroxene and amphibole and moderate grades of quartz, mica, epidote and rutile. Mineral ownership in the deposit is divided in half by property borders, with a western (Vevring) and an eastern side (Engebo).
Arctic Mineral Resources has the extraction rights on the western side, whilst another junior mining company has extraction rights in the east. Exploration in this deposit commenced in 1970s, initially focused on rutile and later on garnet, and includes more than 9 kilometres of core drilling, extensive surface sampling, and geological analysis of the 630m long road tunnel that intersects the deposit diagonally. Our properties contain sufficient resources for mining across generations.
Efficient ore access and advantageous logistics
Vevring and the Engebo mountain is located on Norway’s west coast on the northern banks of the Forde-fjord close to the North Sea. The west coast of Norway is famous for its fjords and the Forde-fjord is declared a national salmon fjord. The garnet and rutile bearing eclogite deposit was discovered in 1968 and explored and analysed from 1978 onwards.
The eclogite deposit is a 2.5 km long east-west trending hill on the northern side of the Forde fjord just east of the local Vevring community. The deposit origins at unknown depths in the west, trending upwards south/south-east before surfacing at sea level west in the picture below, then trending upwards in a north-eastern direction before surfacing at the top and continuing underground to the east.
The rock in this eclogite deposit is considered very competent and favourable for underground mining. Our properties feature efficient and roadless access to high grade ore surfacing in the fjord at sea level. Proximity to the North Sea also grants cost-efficient dispatch and logistics to core markets in Europe.
Mineral values in the Vevring deposit
The sizeable Vevring-Engebo deposit features two minerals of particular commercial interest; garnet (+/-40) and rutile (+/-3%). Garnet is primarily used for sand blasting and water jet cutting whilst rutile is mainly used for pigment manufacturing.
Extensive examination, drilling and analyses have been conducted to determine whether the in-situ rock is suitable for mining stone products, aggregates, and / or industrial minerals. In 1991, the Geological Survey of Norway published a report that concluded that the mineral deposit featured insufficient rutile grades to enable commercially viable rutile mining. Weighted average rutile grain sizes tend to run on the smaller side of what is preferred for pigment manufacturing – something that impacts achievable recovery within markets specifications for purity and impurity. Initial evaluations of the Vevring/Engebo-deposit disregarded the economic potential of garnet. However, as time went by and new players got involved, attention was gradually shifted towards garnet. Today, garnet represents the majority value for both mining companies involved in the deposit. Garnet is the only commercially viable mineral to mine on a stand-alone basis, however, with rutile representing a possible, but not economically necessary, by-product.
Focus on garnet recovery is critical to achieve a sustainable and commercially optimal utilisation of the non-renewable resources in the Vevring-Engebo deposit. Our properties contain in-situ garnet resources for generations worth of mining.
A moderate yearly extraction rate yields significant income per ore tonne
Various companies have developed mine concepts and plans for the Vevring-Engebo deposit. Initially focused on economies of scale and low unit costs at the expense of recovery and sales income per ore tonne. With time it became apparent that this type of approach was neither commercially viable nor sustainable. The initial mine plan in 1997 featured ore extraction rates of up to 12 million tonnes per annum (mtpa), this was followed by 4.0 mtpa in 2009, 1.5 mtpa in 2017 to 0.5 mtpa in the most recent project (2018). To be able to sell all recoverable garnet from start of production one needs to limit extraction rates to around this level. Moderate extraction rates are essential to a sustainable utilisation and an operation with zero waste.
Planned utilisation of garnet at production start – and long-term have been as follows:
- 1997: 0,3% garnet (garnet only featuring as by-product)
- 2009: 2,5% – 12,5% garnet (moderate sales at commissioning, increased sales over time)
- 2017: 9,3% – 17,4% garnet (moderate sales at commissioning, increased sales over time)
- 2018: 19,2% – 22,4% garnet (improved utilisation to follow from increased recovery)
Garnet income per tonne of ore has increased from € 0.4 in the first project to more than € 50 in AMR’s project. In comparison, Norway exports aggregates to Europe at prices of around € 6 per tonne. Recovering and selling garnet will hence yield 8-10 times as high income per tonne and enable solid margins despite higher operating costs from underground mining and mineral recovery as well as higher upfront investments in e.g., mineral recovery equipment compared to that of an aggregate quarry.
From resource to sellable products
The Vevring-Engebo deposit is a large and well-defined deposit featuring high mineral grades and significant in-situ values.
In-situ values represent the gross market value of the minerals a deposit contains. Based on relevant economic factors such as mineral grade, market prices, and general operating costs, a part of the deposit will be defined as an economically mineable resource – on a general basis – and be included in a resource estimate. Resource estimates form the basis for mine planning and calculations of ore reserve estimates. An ore reserve represents a technically and economically recoverable portion of a resource included in a specific mine plan.
It is rarely feasible to plan a mine that turns all resources into reserves. If one were to extract all resources in the Vevring-Engebo deposit, the mountain would be gone. The amount of extractable resource is also determined by the mineral content and operating costs involved in mining a particular resource block. The Vevring-Engebo deposit features high rock mass strength, allowing for a majority of the resource to be extracted through underground mining featuring large stopes and limited resources left for stabilisation purposes, typically referred to as horizontal and vertical pillars.
PRICE PER TONNE
Garnet grain sizes, product quality, and physical and chemical properties are key price factors
Different sizes of garnet grains are used for different things. Large grains are used for heavy blasting, medium grains are used for both blasting and waterjet cutting, and smaller grains are typically used for fine blasting, cutting and polishing. Large grains can cut through thicker surfaces than smaller particles. They also leave more profile / structure in a blasted surface. Smaller grains yield smoother surfaces and sharper cutting edges. There is less supply of large grains hence they tend to command higher prices.
Product purity is another key price determinant. Waterjet cutting, for example, requires grains to be within a narrow size range. Too large grains or too small grains would typically clog the nozzle and stop the entire operation. Chemical composition of the garnet is important too. Industrial garnet refers to garnet that pre-dominantly belongs to a sub-group named Almandine. Furthermore, the formation of the grains in the deposit (millions of years ago) will impact whether grains tend to be durable or brittle. End users disfavour brittle garnet that break upon impact as these may yield dust, particles in the blasted surface and / or poor blasting / cutting performance. Lastly, the physical shape of the garnet may impact performance. Hard rock garnet, such as in the Vevring-Engebo deposit, feature mineral grains with sharper edges than those from mineral sand (alluvial deposits). Sharper edges normally yield improved surface penetration, in turn enabling improved blasting / cutting performance.
EUROPE CONSUMES ALL GARNET SIZES
Had it been easy, it would have already been done…
Garnet in the Vevring deposit tend to be in the medium-to-fine grain size range. Europe utilises finer grain sizes relative to any other end-markets both for historical reasons and due to insufficient supply of alternative abrasive media featuring coarser particle sizes. Focusing on Europe as a primary market is key to an optimal utilisation of garnet from the Vevring deposit.
We have signed a memorandum of understanding with a large industrial minerals company for 100% offtake of all recoverable garnet from start of operations.