The main characters of the animated film are dwarfs living under the ground and looking for different stones there that they consider precious. Dwarves save these jewels in order to place them later in the sky, so it would shine and shimmer much brighter than with ordinary stars. Once a toy pioneer who is fond of geology enters the gnome kingdom. He tells underground dwellers that they shouldn't do that, and talks about the practical benefits of each mineral. Gnomes learn that all their stones, it turns out, are very important for people and are used in the most different branches of their activity.