3" Polished Blue Lace Agate Slice - South Africa

This is a polished slice of blue lace agate collected from South Africa. The blue coloration of this specimen is truly wonderful and vibrant. These chalcedony veins are formed by hydrothermal deposition within large cracks in the Karoo Whitehill Formation. These cracks are caused by a fault that runs through the area.

It comes with an acrylic display stand.

Quartz is the name given to silicon dioxide (SiO2) and is the second most abundant mineral in the Earth's crust. Quartz crystals generally grow in silica-rich environments--usually igneous rocks or hydrothermal environments like geothermal waters--at temperatures between 100°C and 450°C, and usually under very high pressure. In either case, crystals will precipitate as temperatures cool, just as ice gradually forms when water freezes. Quartz veins are formed when open fissures are filled with hot water during the closing stages of mountain formation: these veins can be hundreds of millions of years old.

Agate is a variety of microcrystalline quartz (chalcedony) that displays translucence and, in some cases, banding. Agate primarily forms when silica-rich fluids fill pockets within rocks and/or fossils, depositing the silica along the walls of the rock. This process can result in banding patterns, as the compositions and impurities of these depositing fluids change over time. These banding patterns can either form as flat layers, creating linear patterns known as waterline agate, or as rounded layers, forming more common ring-like patterns. These patterns depend on the surfaces available for deposition.

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DETAILS
SPECIES
Chalcedony var. Quartz
LOCATION
Namibia, Africa
SIZE
3 x 2.6", .8" thick
CATEGORY
SUB CATEGORY
ITEM
#128425