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Onyx

A chalcedony that occurs in bands of different colors and is used as a gemstone, especially in cameos and intaglios. An agate-like stone formed by precipitation in cold mineral springs. It is often translucent with a layered look.

Striped, semiprecious variety of the silica mineral agate with white and black alternating bands. Other varieties include carnelian onyx, with white and red bands, and sardonyx, with white and brown bands. Its properties are the same as those of quartz. Onyx is used in carved cameos and intaglios because its layers can be cut to show a colour contrast between the design and the background. It is found worldwide, but chiefly in India and South America.

Banded chalcedonic quartz, in which the bands are straight and parallel, rather than curved, as in agate. Unfortunately, in the colored-stone trade, gray chalcedony dyed in various solid colors such as black, blue, and green is called onyx, with the color used as a prefix. Because the color is permanent, the fact that it is the result of dyeing is seldom mentioned.

The natural colors of true onyx are usually red or brown with white, although black is occasionally encountered as one of the colors. When the colors are red-brown with white or black, the material is known as sardonyx; this is the only kind commonly used as a gemstone. Its most familiar gem use is in cameos and intaglios.

Onyx, sard, and sardonyx are all varieties of chalcedony (microcrystaline quartz). Onyx comes in brown, white, grey, and black. Sard is a reddish-brown variety. Sardonyx is a blend of sard and onyx with the red bands of sard and the white bands of onyx. Onyx, Sard and Sardonyx all have a hardness rating of 7.Onyx is very similar to agate. Onyx has straight bands of brown, white or black; agate has curved lines of many colors.

Since ancient times, Onyx has been dyed to improve it's color. Often treated agate is sold as Black Onyx. Onyx may chip or scratch rather easily and is found worldwide. Onyx is the Mystical birthstone for the month of December. It is also the birth stone for the Zodiac sign of Leo.

Onyx is a protective stone worn when facing adversaries in battles of conflicts of all kinds, or while hurrying down a dark street late at night. In classical ceremonial magic, the image of the head of the god Mars or a figure of the hero Hercules was engraved on onyx and carried for courage. Indians and Persians believed that wearing onyx protected them from the evil eye, and that placing onyx on the stomach of a pregnant woman in labor would reduce the labor pain and bring on earlier delivery.

Onyx is not only used for protection, but also as defense against negativity consciously directed towards you. It has also been used to reduce uncontrollable sexual impulses. The close union and yet strong contrast between the layers of black and white in some varities of onyx may suggest its connection with romance. In India, Gemologists recommend Onyx as a protective measure for harmonious relationships, thus keeping away any probability of disturbances or differences between the couple.

Onyx requires little care. It is a hard and durable stone.

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