Natural History, including Gorgosaurus
Natural History, including Gorgosaurus
No reserve
Auction Closed
July 28, 03:27 PM GMT
Estimate
2,000 - 3,000 USD
Lot Details
Description
Grape Agate
Mamuju Regency, Sulawesi, Indonesia
12 by 9 by 4 inches (30.5 x 22.9 x 10.2 cm).
A large specimen of amethyst that consists of “balls” of microscopic acicular crystals grouped together in grape-like bunches. The terminations of these crystals can be seen in the sparkly druzy surface around the specimen, and is especially noted in the vug in the center.
Often used in jewelry, amethyst is a type of lavender quartz deriving its purple hues from iron impurities, traces of other elements, and exposure to radiation. Displaying a dazzling complex crystal lattice pattern, the name amethyst comes from the Greek word for "intoxicate".
While quartz (silicon oxide) may be the second most common mineral present in the Earth’s crust, many rare and unusual varieties offer opportunities for collectors. From the royal purple and golden hues of amethyst and citrine, to the intense turquoise and apple green of chrysocolla and chrysoprase, quartz has an incredible spectrum of available colors. Rare and unusual crystal forms such as scepters, gwindels, faden, elestial and “spirit” quartzes create incredibly diverse aesthetics. As a prime component within many of the great crystalline environments, quartz is also a frequent partner to and basis for other mineral growth.