Research Results For 'Chalcedony'

AGATE

Agate is a semi-precious stone siliceous semi-pellucid compound mineral, consisting of bands or layers of various colours blended together, the base generally being chalcedony, and this mixed with variable proportions of jasper, amethyst, quartz, opal, heliotrope, and carnelian. The varying manner in which these materials are arranged causes the agate when polished to assume some characteristic appearances, and thus certain varieties are distinguished, as the ribbon agate, the fortification agate, the zone agate, the star agate, the moss agate, the clouded agate, etc. In Scotland they are cut and polished under the name of Scottish pebbles.
Research Agate

BLOODSTONE

Bloodstone is a dark green variety of chalcedony sprinkled with red jasper, hence the name.
Research Bloodstone

CARNELIAN

Carnelian is a clear red chalcedony, a semi-precious gemstone, consisting of quartz with iron impurities which give it a translucent red colour.
Carnelian is found mainly in Brazil, Japan and India.
Research Carnelian

CAT'S-EYE

Cat's eye is a variety of quartz or chalcedony, exhibiting opalescent reflections from within, like the eye of a cat. The name is given to other gems affording similar effects, especially chrysoberyl.
Research Cat's-Eye

CHALCEDONY

Chalcedony is a cryptocrystalline, translucent variant of quartz comprised of silica, having usually a whitish colour, and a lustre nearly like wax.
Chalcedony was named after Chalkedon, near Istanbul. It was traditionally used for decorative objects and amulets. It has a relative hardness of 7. When chalcedony is variegated with spots or figures, or arranged in differently coloured layers, it is called agate; and if by reason of the thickness, colour, and arrangement of the layers it is suitable for being carved into cameos, it is called onyx. Chrysoprase is green chalcedony; carnelian, a flesh red, and sard, a brownish red variety.
Research Chalcedony

CHRYSOPRASE

Chrysoprase is a green variety of chalcedony, coloured by nickel. When heated or exposed to sunlight the mineral often becomes paler, the colour being restored after exposure to moisture. It is a brittle mineral and is inclined to crack in cutting or setting. It is often extremely beautiful, so that it is much esteemed in jewelry. It is translucent, or sometimes semi-transparent, and of a hardness a little inferior to that of flint.
Research Chrysoprase

JASPER

Jasper is an opaque, cryptocrystalline variety of quartz that takes a high polish and is used as a gemstone. It is usually stained by impurities and occurs in various colours, such as red, green, yellow, and blue. When the colours are arranged in bands, the mineral is called riband jasper; a variety containing alternating bands of red and green is known as Siberian jasper. Mottled yellow or brown varieties of jasper are called Egyptian jasper. Agate jasper is intermediate in structure between true jasper and chalcedony . Inclusions of red jasper occur in heliotrope. The jasper mentioned in the Bible as one of the stones in the breastplate of the high priest and as the foundation of the wall of the New Jerusalem is believed to have been a dark green, opalescent stone. The jasper of the ancients was a partially translucent stone, probably containing some chalcedony and a variety of the latter known as chrysoprase.
Research Jasper

ONYX

Onyx (named on account it resembles the colour of a fingernail) is a variety of chalcedony, similar to agate but featuring straight, rather than curved bands.
Research Onyx

SARD

Sard is a brownish red variety of Chalcedony.
Research Sard

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