For decades, Luigi Lineri has toiled along the Adige river in northern Italy where he has amassed an astonishingly vast treasure trove: rocks. A research endeavour, an artistic undertaking and even a form of time travel, this beautiful quest defies rigid categorisation. Guided by Lineri’s indefatigable passion, Giuseppe Petruzzellis’s meticulous documentary lends an ear to what the stones have to say.

Using title cards of white text over a black screen, the film divides Lineri’s collection into a myriad of themes. While some pebbles point to the technical evolution of tools in prehistoric times, others bear the artistic traces left behind by human creativity. There’s a streak of the existential and the metaphysical as well. From egg-shaped relics to stones that resemble genitalia, the origins of life on Earth are wondrously embedded into these inanimate objects. In making a home for these wandering pieces of history, Lineri movingly describes the space as a shrine, a dedication rich with spiritual significance.

The fluid cinematography further heightens the atmosphere of awe and mystery. The camera lingers closely on Lineri’s nimble fingers as he tenderly handles various items, his careful gestures transforming silent rocks into living, breathing beings. After focusing on individual items on the shelves where they rest, the film gradually pulls back to reveal the sheer scale of Lineri’s holy sanctum.

The sonorous soundscape, however, is later disrupted by noises coming from the deforestation of local land. If stones are witnesses to human interconnectedness to our own past and nature at large, Petruzzellis emphasises how fragile this relationship is. As pebbles and sand are being cleared for development projects, not only has the Adige been forced to alter its course, but a part of history has forever been wiped from its shores.

• La Ricerca is on True Story from 29 November.