An impressive and substantial specimen of native sulfur from the historic Cozzo Disi Mine, Casteltermini, Agrigento, Sicily, Italy, one of the most famous localities of the classic Sicilian sulfur deposits. The specimen presents an exceptionally rich crystallized surface, with numerous bright yellow sulfur crystals distributed across a strongly three-dimensional matrix. The abundance of crystals, their characteristic sulfur-yellow color and the sculptural architecture of the specimen give the piece a remarkable visual presence. With dimensions of approximately 28 × 17 × 15 cm (11.02 × 6.69 × 5.91 in) and a weight of approximately 6 kg (13.23 lb), this is a particularly substantial display specimen. One of its most interesting characteristics is its strong response under 365 nm UV light. The associated matrix exhibits intense fluorescence and, once the UV source is switched off, a clearly visible phosphorescent afterglow. This adds an entirely different appearance to the specimen when viewed under UV and in darkness immediately afterward. The specimen has been carefully cleaned under laboratory conditions to reveal the crystalline surfaces while preserving its natural mineralogical character.