When I first arrived in Soriano nel Cimino, I thought the peperino was ugly. Rough, splotchy stone that looked like it had bird poop splattered all over. But by the end of the week, I had fallen in love with the peperino.
When you think of Italian sculpture and other works of art that are carved from stone, you most likely think of marble. Not all regions of Italy had a ready supply of marble to cut from the ground. Wile much of Italy has stone underfoot, the stone varies in color and quality from one region to another. Soriano nel Cimino – on the side of the Monti Cimini – a (hopefully) dead volcano – you have ground that is pyroclastic stone formed from the ash that spewed from the volcano eons ago.
This particular stone is medium to light gray in color and dotted with random white splotches. The peperino is a medium grain stone, rougher than the fine grain of marble. Despite not being the loveliest stone, it was carved into art simply because it was what was available. Importing marble was an expensive endeavor.
Most interestingly, Peperino is porous. It has rougher grain than marble, but that rougher grain is because of tiny holes, which allow water to seep through the stone. You find peperino carved in it;s original location where it was formed long ago, instead of being cut away form the ground and moved to a specific location. Peperino stone fountains were carved where there was already water flowing naturally out of the stone. The fountains designed to make the most of the natural water path.
Besides being an excellent choice for fountains, peperino was used for outdoor sculptures because it is resistant to being worn away by rain and wind. Marble sculptures require protection from the elements since marble is a relatively soft stone. The splotchy white & gray coloring of the peperino makes is easily identified. And once you get adjusted to looking at sculptures carved from a rougher stone, spotting it while exploring cities and gardens, is delightful.
The Palazzo Chigi-Albani in Soriano nel Cimino, Italy has excellent peperino carvings including natural fountains. The Villa Lante near Bagnaia, Italy also has peperino fountains and carvings.
— Update: we now have T-shirts with fountain designs from the Villa Lante