Dims: 11.0 x 11.0 x 7.6" (27.9 x 27.9 x 19.3 cm)
Wt: 12.1 lbs. (5.5 kg)
Minas Gerais, Brazil
This specimen consists of a conical section of a geode which is made up almost entirely of Citrine. The crystals are in the form of a druse that once lined the inside of an air bubble in lava. They originated as amethyst, but heat-treatment turned them a deep orange-yellow coloration and caused most of the lava skin to flake off. Being sheltered inside a depression, almost all of the crystals are undamaged and in pristine condition. The largest achieve lengths of nearly 2" (5 cm) and diameters of 1" (2.5 cm). All have excellent hexagonal prismatic form, though their prism faces and edges are mostly obscured or destroyed by intergrowth. Their edges are very well-defined, and their faces are clean, smooth, and possess the standard vitreous luster. They are transparent, though most of their clarity is hampered by severe internal fracturing. Among the Citrines are many white calcites- some of these have a nearly "nail head" form, though all are intergrown into clusters and rather warped. They have a dull waxy luster and are translucent at best.