3.5" Amethyst Crystals on Sparkling Quartz Chalcedony - India

 
 
This is a stunning, 3.5" wide specimen that features amethyst crystals that formed over druzy quartz chalcedony, collected from Madhya Pradesh, India. This formation occurred within a cavity/vug in the basalt host rock. Apophyllite, barite, chabazite and julgoldite crystals have also been reported as being present within some of these vugs. Based on the luster and striations of the additional colorless crystals within this cavity, it is likely that they're apophyllite.

Comes with an acrylic display stand.

Amethyst is a purple variety of quartz (SiO2) and owes its violet color to natural irradiation, iron impurities, and the presence of trace elements, which result in complex crystal lattice substitutions. It’s considered a semi-precious gemstone, and just two centuries ago was considered to have a value on par with diamonds, sapphires and rubies. The largest and best known amethyst deposits occur in southern Brazil and Uruguay but many localities around the world produce an amazing variety of amethyst crystals and formations.

Chalcedony is any microcrystalline variety of silica composed of very fine intergrowths of quartz and moganite. Microcrystalline meaning the crystals are microscopic and cannot be observed by the naked eye. Both quartz and moganite have the same chemical formula SiO2 (silicon dioxide) but different crystal structures. When free from impurities, chalcedony is colorless and transparent. Dependent on impurities present during formation, chalcedony can form in a wide variety of colors including red, yellow, green, blue, purple, grey, white and numerous color hues in between. Chalcedony is quite hard, being a 7 on the Mohs Hardness Scale, which makes sense considering quartz is the benchmark mineral for a 7.

DETAILS
SPECIES
Quartz var. Amethyst & Quartz var. Chalcedony
LOCATION
Khadakwani, Madhya Pradesh, India
SIZE
3.5 x 2.5"
ITEM
#168764