8.8" Stilbite, Apophyllite, Calcite and Quartz Association - India

 
 
 
 
 
 
This is an incredible 8.8" wide mineral association, containing stilbite, apophyllite, quartz druze and a beautiful, large calcite crystal. This was collected from Nashik in Maharashtra, India. The stilbite is translucent, with some faint pink coloration. Most of the apophyllite formed as double terminated crystals with brilliant luster and clarity. Quartz druze can be found surrounding all of the small stalactitic projections, and there is a massive, slightly yellow calcite crystal cluster in the center of the specimen. A truly wonderful specimen, perfect for any mineral collection.

Stilbite is probably the most common zeolite found in these deposits. Crystals often form flowery, bowtie or hourglass shaped structures and come in a variety of colors. Some of the most beautiful colorations are the pink or peach tints. Apophyllite while not a zeolite itself is almost always found associated with zeolites in the same pockets. It has two crystal habits, a rectangular prism capped by a steep four sided pyramid or a pseudo-cubic structure. While not a well known mineral to the general public it is popular among mineral collectors due to it's pastel colors and beautiful crystal formations.

Calcite, CaCO3, is a carbonate mineral and the most stable polymorph of calcium carbonate. The other polymorphs are the minerals aragonite and vaterite. Calcite crystals are trigonal-rhombohedral, though actual calcite rhombohedra are rare as natural crystals. However, they show a remarkable variety of habits including acute to obtuse rhombohedra, tabular forms, and prisms. Calcite exhibits several twinning types adding to the variety of observed forms. It may occur as fibrous, granular, lamellar, or compact. Cleavage is usually in three directions parallel to the rhombohedron form. Its fracture is conchoidal, but difficult to obtain.

Silicon Dioxide, also know as SiO2 or Quartz, is the second most abundant mineral in the Earth's crust. Quartz crystals generally grow in silica-rich, hot watery solutions called hydrothermal environments, at temperatures between 100°C and 450°C, and usually under very high pressure. Quartz veins are formed when open fissures are filled with hot water during the closing stages of mountains forming, and can be hundreds of millions of years old.
DETAILS
SPECIES
Stilbite, Apophyllite, Calcite & Quartz
LOCATION
Nashik, Maharashtra, India
SIZE
8.8" wide, 6" deep, 2.1" tall
CATEGORY
SUB CATEGORY
ITEM
#65718