GP-suite granitic dyke crosscutting metavolcanic rock in Bergslagen. Hammer is 80 cm long.
Photo: Edward Lynch, SGU.
Characteristics of granite in Bergslagen can show the way to findings of tungsten
Unique characteristics of certain granites in the western Bergslagen ore district in Sweden can be a clue in the search for critical raw materials such as tungsten and fluorspar. This is shown in a new report from the Geological Survey of Sweden (SGU).
In the western parts of the Bergslagen ore district in Sweden there are more than 100 known deposits with mineralisation of tungsten, molybdenum, fluorspar, and copper. A study carried out by SGU now confirms that many of these mineralisation’s are connected to granites in the so-called GP suite.
– The granites closest to the mineralisation show unique textural, mineralogical, petrophysical, and geochemical features compared to those further away, says Edward Lynch geologist at SGU.
These features arose during the formation process of the granites 1.8 billion years ago and can today be a tool for exploration companies to find the "right type of granite" when searching for certain critical raw materials like tungsten and fluorspar in the Bergslagen area, or in other similar parts of the Swedish bedrock.
Both tungsten and fluorspar are classified as critical raw materials by the European Union due to their economic importance together with the high risk of supply disruptions. Since January 2021, tungsten is also classified as a so-called conflict mineral, which means that EU-based industries should avoid importing tungsten from politically unstable regions. Molybdenum is not currently assessed as critical by the EU but is one of several metals that are considered important for the European defence industry.
Last reviewed 2023-09-19