This specimen is Calcite (CaCO₃), crystallized in the trigonal crystal system and displaying the classic Palmital habit: intergrown, sharply defined rhombohedral crystals arranged in a rosette-like cluster. Its warm honey-to-amber coloration is typical of Palmital calcites and results from trace elements incorporated during growth. Geologically, the crystals formed from carbonate-rich hydrothermal fluids circulating through fractures in limestone and metamorphic host rocks, precipitating in layered stages that produced the thick, sculptural crystal blades and softly frosted luster seen here.

The Palmital region of São Paulo became an important source of collectible calcite in the mid-20th century, especially during the 1960s, when quarrying exposed exceptional crystal pockets. Specimens dating to circa 1964 belong to an early generation of Brazilian calcites that entered European and American collections before widespread commercial exporting, and are now regarded as heritage pieces within Brazilian mineralogy. Adding to its appeal, this calcite exhibits golden-yellow fluorescence under longwave UV light, caused by manganese activation, which highlights internal growth zoning not visible in daylight. Together, these qualities make the specimen a refined balance of aesthetic form, geological significance, and optical beauty.

**Specimen from historic collection of Luiz Menezes, one of Brazil’s most respected mineral collectors from Brazil**

Approximate measurements: 54.98 x 42.93 x 36.29 mm

Weight: 82.00 g