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Celestine

Celestine

Celestine is named after the Latin word caelestis, meaning “heavenly.”  It is a mineral consisting of strontium sulfate. The mineral is named for its occasional delicate blue color. Celestine occurs as crystals, and also in compact massive and fibrous forms. It is mostly found in sedimentary rocks, and often associated with the minerals gypsum, anhydrite, and halite.

Celestine is also known as celestite.  It is a transparent to translucent mineral.  It is found on sedimentary rocks, like limestones.  Celestine is used in fireworks, as an additive to battery lead and in the manufacture of rubber and paint.  It is also used in the nuclear industry, in sugar beet refining, and in the preparation of iridescent glass and porcelain. The most attractive crystals are pale sky blue, but colorless celestine is also common.  Its perfect cleavage makes it very fragile, but it is cut for the collector. Faceted crystal comes from Majunga, Madagascar.
Best celestine crystals are found in Lake Erie (United States), Bristol (England) and Sicily (Italy), also in Madagascar, Mexico and Canada.   It is mined in England, Russia and Tunisia
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Chalcedony

Chalcedony

Chalcedony is a variety of microcrystalline quartz (silicon dioxide), often with some iron and aluminum.  It is composed of microscopic fibers.  Chalcedony is found in veins, geodes, and concretions.  It can be mammillary, botroyoidal, or stalactitic.  Chalcedony is found in numerous locations throughout the world.

 Its name may derive from the ancient port of
Its name may derive from the ancient port of Khalkedon in Asia Minor known today as (Turkey).
The word Chalcedony covers a group of quartzes, including agate, petrified wood, chrysophrase, bloodstone, jasper, carnelian, moss agate, and sard.  When pure, chalcedony has its own distinct properties.  It is translucent and has a white or bluish color, but it may be colored green by chromium. Chalcedony is formed in several environments, generally near the surface of the earth where temperatures and pressures are relatively low.
Apple-green chalcedony is called chrysoprase; dark red or orange-red to reddish brown chalcedony is called carnelian; dark green spotted with red inclusions is called heliotrope (bloodstone); distinctly banded specimens, in which adjacent bands differ in color and in degree of translucency, are called agate; and mottled yellow, red, brown, or green chalcedony is called jasper.
Good quality chalcedony is found in Brazil, India, Madagascar and Uruguay.  Its fibrous structure gives chalcedony its toughness and makes it ideal for carving, especially in Germany where it is very popular.  Because of its porous , it may be dyed with a variety of metallic salts.