In the Hall of Mirrors on the first floor, the exhibition PALEOLITHIC AVANT-GARDES. Visions from Giottolandia, the Lithic Art Gallery of Tuscia by Roberto Mari will be inaugurated.

"The 'pictures' displayed in this exhibition are macrophotographs of details of pebbles collected in some areas of central-southern Tuscany and upper Lazio.

When I discovered the first ones in 1988 I started calling them “giottoli” in honor of the painter Giotto these pebbles (in Italian “ciottoli”) that showed on their surface an incredible variety of designs and colors. Tens of thousands of images of "beautiful" stones are published on the web, from all over the world, from collectors to museums, but none of these specimens even come close to the chromatic-figurative richness of the giottoli, so up until now it would seem that in the entire planet these "painted" stones can only be found in this area corresponding roughly to ancient Tuscia. But perhaps it is even more curious that the only existing documentation of these very singular stones in the world is represented by my collection of about three thousand specimens. In many of these you can see "pictorial" details of remarkable beauty, of which the "visions" presented here should therefore be considered only a small example.

I have never sold any of the jewels that I have been lucky enough to find, because I believed that the great wealth of aesthetic results that they represent as a whole should not be lost and for this reason I have always thought of their public and museum destination. This exhibition is therefore for me above all the opportunity to publicly communicate my intention to donate my entire collection to public or private entities that undertake to permanently exhibit at least a part of it.

Roberto Mari

"Colorful like palettes, mysterious like ancient geological maps: the Giottoli are natural masterpieces that tell a long and fascinating story of the Earth. Discovered only in 1988 along the coasts and riverbeds of the Maremma region, these pebbles are named after Giotto, the great medieval painter, because of the richness and harmony of their colors. No brush ever touched them—they are artworks shaped by time, chemistry, and the shifting of Earth’s crust. 

What makes them so special?

A surprising geological origin
Born as fine-grained sedimentary rocks, they fractured during tectonic events and were later “healed” by nature, forming unique textures like natural mosaics.

A double natural transformation
First, a deep alteration caused by underground fluids and pressure. Then a second, more surface-level phase during their journey as pebbles transported by rivers and waves.

Rich and natural colors
From rusty reds to deep greens, their colors come from iron oxides, black manganese dendrites (like ink drawings), and bluish-purple hues caused by copper sulfates.

A natural artistic approach
Unlike other famous Tuscan stones like Pietra Paesina or Verde d’Arno, the Giottoli aren’t cut but gently polished by hand—letting the natural surface patterns tell their story.

[...]

Let yourself be captivated!

The Giottoli are more than just stones: they are stories you can touch. Observing them means reading the traces of vanished oceans, rising mountains, and the climate cycles that shaped our planet. An exhibition to rediscover the artistic soul of geology."

Alba Patrizia Santo - Department of Earth Sciences, University of Florence