Sormuskivi erratic boulder
Location
- Tassiantie 1-3 54230 Lappeenranta Navigate
![](https://www.lakesaimaa.fi/wp-content/uploads/2023/10/e5591080-6e81-11ee-9fca-6fdb01d69922-443x375.jpeg)
Sormuskivi is one of Finland’s largest erratics – its greatest visible dimensions are 8m x 8m x 7m, and some of the erratic is underground. The erratic boulder consists of rapakivi granite - viborgite, to be more specific - with characteristic light plagioclase halos surrounding round grains of potassium feldspar.