Super specimen HQ grape agate Crystal cluster - Height...

Grape agate is the commercial trade name for a rare, unique form of botryoidal (cluster-shaped) purple chalcedony, a microcrystalline variant of quartz. The most sought-after varieties range from soft lilac and lavender to deep dark purple. The color arises from traces of iron and manganese within the crystal structure. Sometimes the spheres have a microscopically thin layer of sparkling crystal points, which creates a beautiful 'druzy' glitter effect. Unique locality: The vast majority of quality grape agate was discovered only around 2014 and is mined exclusively in the Mamuju region on the island of Sulawesi in Indonesia. The mineral forms deep in the cavities of volcanic rock (andesite). For millions of years, silica-rich fluids have layered themselves in perfect spheres around a central point. Hardness: It has a score of 6.5 to 7 on the Mohs hardness scale. The loose spheres, however, can be fragile and break with rough handling.

Estimación:€250

Ver todos los artículos deCatawikioEtnográfica