6.8" Agate Nodule on Metal Base - Brazil

This is a gorgeous half nodule of agate from Brazil with a deep central quartz crystal pocket. It has been cut and polished on one face to highlight the banding. Light purple and blues with reduced banding work with the large crystals to make an awesome display.

This nodule sits snuggly in a custom metal display stand that is is removable.

Agate is a translucent variety of microcrystalline quartz. Agate primarily forms when silica-rich fluids fill pockets within rock and/or fossils, depositing it along the walls of the rock. This process can result in banding patterns as fluid compositions and impurities change over time. These banding patterns can either form as flat layers, forming agates known as waterline agates, or as concentric layers typical of most agates, depending on the surfaces available for deposition.

Agate has also been known to fill veins or cracks in volcanic rock. Such agates, when cut transversely, exhibit a succession of parallel lines giving a banded appearance to the section. Such stones are known as banded agate, riband agate and striped agate.

Agates from Brazil are mined from decomposed volcanic ash and basalt from the late Permian age (248-275 million years old). In Rio Grande do Sul, the agate "mines" are normally just plowed fields in which loose agates are found and collected. These agates can be very colorful and polish beautifully.
SOLD
DETAILS
SPECIES
Chalcedony var. Agate
LOCATION
Brazil
SIZE
6.8 x 4.7" (without base), about 2.6" thick, 9.6" tall on stand
CATEGORY
SUB CATEGORY
ITEM
#206875