Graphite

Flake graphite is an important raw material for lithium-ion batteries. More information on graphite and Finnish graphite surveys can be found e.g. in GTK websites.

Graphite studies in southern Savo

Much of the bedrock of southern Savo (e.g. the eastern parts of Mikkeli, the southern parts of Juva, Sulkava, Puumala) represents a high degree of metamorphism, granulite facies (Fig. 1), i.e. the rock types in the area have undergone changes caused by high temperatures. As a result, mineral growth has been strong and the rock types are coarse-grained. The bedrock of southern Savo contains graphite-rich layers, as is generally the case elsewhere in Finland. However, due to the granulite facies metamorphism, the actual black schists (fine-grained graphite-rich schist) do not occur, and the graphite in these carbon-rich layers is coarse flake graphite (Fig. 2). From these points of view, the area’s flake graphite potential is good.

The graphite surveys in southern Savo are in the early stages and the surveys are now aimed at delimiting the best areas. Suomen Malmitutkimus Oy has made an application for reservation notification in the first study area (Fig. 3).

Figure 1. Southern Savo graphite study area (circle) on the metamorphic map. The grey area marks the high grade, granulite facies metamorphism. Figure produced from the GTK MDaE map service.
Figure 2. Flake graphite in a bedrock sample in southern Savo.
Figure 3. Application for reservation notification in the graphite study area. Figure produced from the GTK MDaE map service 30.05.2020.

Graphite studies in Ostrobothnia

Terrains of high metamorphic grade exist also in Ostrobothnia, like in the municipality of Siikalatva, between Rantsila and Pulkkila. Flake graphite potential is therefore good in the area. During the bedrock studies by the Geological Survey of Finland in 1990’s, graphite-rich rock was found in the area, both in outcrops and in bedrock drilling. Preliminary studies of the bedrock samples indicate that graphite occurs as coarse flakes.

Suomen Malmitutkimus Oy has made in January 2021 a reservation notification, named Kupukka, in the area (Fig. 4).

Figure 4. Application for reservation notification in Siikalatva. Figure produced from the GTK MDaE map service 8.2.2021.