The waters of the Jurkiškis stream, which had washed away the valley's slopes for a long time, washed away a large number of boulders of one size or another, most of which lie in the riverbed. Here we will find boulders of 0.5 m - 1 m and larger. The largest of them reaches a girth of more than 5 m. This stone is called Jurkiškis stone. It is also called the "Child of Puntukas".

Geologists have found that this boulder, according to its mineral composition, is granite, which belongs to the group of rapa granites. It is probably the most common rock in the form of boulders in our quaternary sedimentary column. Three-quarters of these rocks consist of potassium feldspar and one-fourth of quartz and biotite. This type of granite rock is common in southern Finland, so there is no doubt that it has been dragged to our lands by glaciers for about 1,000 km, and the streams have washed it out of the slope of its canyon valley.