Whetstones have been quaried in Finland for centuries. These come from the village of Västilä, and are marketed by Wästikivi. You can visit the company webpage. The stones are used with water, and quickly form a slurry or paste that improves the performance. These are quite fine, and measure about 4" long, 15/16" wide and 5/16" thick. They are suitable for basic sharpening, and could be followed by the Viking stone above for polished shaving edge.