The discovery of a cup of 'Etna type' in the area of Comiso, among local ceramic objects led to the discovery of commercial trades with the Castelluccio sites of Paternò, Adrano and Biancavilla, whose graves differ in making due to the hard basaltic terrain and also for the utilization of the lava caves as chamber tombs. In the area around Ragusa, there have been found evidences of mining among the ancient residents of Castelluccio; tunnels excavated by the use of basalt bats allowed the extraction and production of highly sought flints. Some dolmens, dated back to this same period, with sole funeral function, are found in different parts of Sicily and attributable to a people not belonging to the Castelluccio Culture." The Sicelian' polytheistic worship of the ancient and native chthonic, animistic-cult deities associated with geysers known as the Palici, and/as well as the worship of the volcano-fire god by the name of Adranos, were also worshiped throughout Sicily by the Elymians and Sicanians. Their (Palici) centre of worship was originally based on three small lakes that emitted sulphurous vapors in the Palagonian plains, and as a result these twin brothers were associated with geysers and the underworld. There was also a shrine to the Palici in Palacia, where people could subject themselves or others to tests of reliability through divine judgement; passing meant that an oath could be trusted. The mythological lineage of the Palici is uncertain. According to Macrobius, the nymph Thalia gave birth to the divine twins while living underneath the Earth. They were most likely either the sons of the native fire god Adranos, or, as Polish historian "Krzysztof Tomasz Witczak" suggests, the Palici may derive from the old Proto-Indo-European mytheme of the divine twins. Mount Etna is named after the mythological Sicilian nymph called Aetna, who might have been the possible mother to the Palici twins. Mount Etna was also believed to have been the region where Zeus buried the Serpentine giant Typhon, and the humanoid giant Enceladus in classical mythology. The Cyclopes, giant one eyed humanoid creatures in classical Greco-Roman mythology, known as the maker of Zeus' thunderbolts, were traditionally associated with Sicily and the Aeolian Islands.