To meet the increasing demand for lithium compounds, new lithium-bearing deposits are being explored worldwide to determine their economic potential. The lithium deposit in Zinnwald/Cínovec is a cross border deposit and one of the largest lithium deposit in Europe.
Picture: Ingenieurgesellschaft Falasch mbH
Chemical composition of Zinnwaldite
- Lithium 1.59 %
- Potassium 8.94 %
- Aluminum 12.35 %
- Iron 12.78 %
- Fluorine 6.52 %
- Rubidium 0.95 %
- Cesium 0.04 %
- Manganese 0.9 %
- Other (Si, O, H) 55.93 %
Deposit and Resources
The deposit at Zinnwald contains an NI43-101 compliant Measured + Indicated Resources of approx. 125,000 t lithium. This corresponds to approx. 650,000 t Li2CO3 (LCE). At a planned underground mining capacity of approx. 570,000 t per year, this guarantees an economic operation of the deposit for more than 30 years.
Mining and mechanical processing
Access to the underground mine will be via an approximately 2 km long ramp.
The portal of the ramp is in immediate vicinity to the processing site in Altenberg. At Altenberg, the ore is crushed and grinded and Zinnwaldite is concentrated and separated from the remaining rock via magnetic separation. The mechanical processing plant has a capacity to produce 132,000 t/a Zinnwaldite concentrate.
In March 2011, Deutsche Lithium GmbH received permission from the Saxon Mining Authority in Freiberg to explore the lithium-tin-tungsten deposit in Zinnwald-Georgenfeld. The work of Deutsche Lithium GmbH refers exclusively to the German part of the deposit in Zinnwald/Cínovec. Since 2011, extensive geological exploration work on the deposit (23 diamond drill holes, up to 400 m depth), bulk ore sampling for mechanical and metallurgical processing testworks, as well as chemical production of lithium compounds was carried out by Deutsche Lithium.
In October 2017, the Saxon Mining Authority granted Deutsche Lithium the mining permit according to §8 BBergG for the deposit in Zinnwald. As a result, the Deutsche Lithium GmbH has the permission to mine the lithium contained within the lithium-mica-greisen ore bodies from the deposit in Zinnwald.
approx. 125,000 t Lithium
The chemical process is divided into the four process steps:
- Calcination of the Zinnwaldite concentrate and additives at about 1,000 °C,
- Aqueous leaching of the roasted product in hot water,
- Precipitation of poorly soluble Lithium fluoride by adding Potassium fluoride,
- Crystallization of Potassium sulfate (SOP) as a by-product from the residual solution.
The expected production capacity is approx. 5,000 t/a Lithium fluoride (approx. 7,000 t/a LCE) and approx. 32,000 t/a Potassium sulfate (SOP).