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, creating a beautiful 'druzy' glitter effect. Unique locality: The vast majority of high-quality grape agate was only discovered around 2014 and is mined exclusively in the Mamuju region on the island of Sulawesi in Indonesia. The mineral forms deep inside cavities of volcanic rock (andesite). Over millions of years, silica-rich fluids have deposited in perfect spheres around a central point in layered fashion. Hardness: It scores 6.5 to 7 on the Mohs scale. The loose spheres can, however, be fragile and break with rough handling.

估價:$278.99

查看所有物品來自Catawiki或Ethnographic