This is a cave inside a large depression presumably due to the collapse of the vault of a larger cave (one of the innumerable) that developed during the 1991/3 eruption. This cave is quite interesting for its morphology, despite not being particularly significant in its development. It is easily accessed from two entrances, positioned in a south/NE direction. The easiest entrance, the one located to the northeast, leads to a lava channel characterized by two lava rolls covered by a multitude of flakes that, when passed through, resemble broken shards. Hence the provisional name given.
After about 15 meters a very large and quite high room opens up (3/4 meters on average). On the left there is a large collapse opening, on the right you access through a small ramp to a fork that allows the visit to 2 channels, however rather low and that do not seem to offer further development after a few meters. There are few phenomena of remelting, while on the floor there are interesting phenomena of "blisters" (lava bubbles) clearly visible.

Another section of the cave is located in a northerly direction, approximately 25 metres away and extends for around fifteen metres.
Given the position quite close to the passage track that leads to path 727 (Serra del Salifizio – Acqua Rocca degli Zappini) it is believed that the hypogeum in question may be known, but little known, in any case it would not be registered or registered. If it were, we invite you to make any reports. In any case, the cave is believed to be of great interest for those who follow the track in question before going up to the Faggi gully.