Onyx details

Onyx was very popular with the ancient Greeks and Romans.The name comes from the Greek word onux, meaning fingernail. The story is that one day frisky Cupid cut the divine fingernails of Venus with an arrowhead while she was sleeping. He left the clippings scattered on the sand and the fates turned them into stone so that no part of the heavenly body would ever perish.
True, black isn't normally the color one associates with fingernails. But in Greek times, almost all colors of chalcedony from white to dark brown and black were called onyx. Today when we think of onyx we often preface the word with black to distinguish it from other varieties of onyx that come in white, reddish brown, brown and banded. Later, the Romans narrowed the term "onyx" to refer to black and dark brown colors only.
Most Black Onyx that is commercially available today is color enhanced (heated and dyed) to increase it's depth of color, although this process does not decrease it's value in any manner.

Scientific Properties

Mohs Hardness of 7 with a trigonal crystal structure.
Although onyx, sard and sardonyx are all varieties of chalcedony, onyx is similar to agate, with straight rather than curved bands. These bands may be brown and white or black and white. Sard is a brownish red variety, sardonyx is a blend of sard and onyx and therefore has the straight white bands of onyx and the brownish red color of sard.
Onyx is mined in Brazil, India, California and Uruguay. It has a fine texture and black color; however some onyx also displays white bands or ribbons against a black or brown background and again, this variety is known as sardonyx.

Mystical Properties

Onyx is thought to increase regeneration, happiness, intuition and one's instincts. It is also told to decrease sexual desire, and to aid in changing bad habits.
The shapes or patterns that onyx holds inside it have led some to suggest that Onyx has a picture in it that tells a story or carries a lesson. Lore tells us that an onyx will retain memory of the physical occurrences surrounding a person. A strong stone to use in psychic work as it tells the story of the wearer.
A strength-giving stone, good for athletes or people under extreme mental and emotional stress. It brings balance to mind or body as well as strength of mind. Onyx is a wonderful stone for those who are flighty by nature, as it will help ground and focus your attention. A strengthening stone that can help you approach a lesson or task with greater self-confidence. It is highly recommended that Onyx be used in conjunction with pearls and diamonds to increase their own metaphysical qualities.

Healing Properties

Onyx must be laid directly on the body or worn over a long period of time as it's power develops quite slowly. It is known to be particularly helpful with skin ailments, healing infected wounds as well as fungal infections, inflammation and even sunburn. Pat the affected skin with onyx water several times during the day and cover with an onyx water compress at night. Due to the fact that onyx needs time to develop its full power, it should be discharged once a week under running water, and if used for a long period of time, it should be placed in the earth overnight once a month. This will regenerate it to help keep it's energy strong.

Magical Properties

Energy: Projective
Element: Fire
Deity: Mars
Associated Stone: Diamond
Powers: Protection, defensive magic, reducing sexual desires
Ancient magic lore tells us that in times long past, onyx was thought to be the manifestation of a demon imprisoned in the stone. This demon would awake in the night and spread terror and nightmares to any persons within its range of influence.
Since antiquity, though, onyx has been known to actually be used as protection against black magic, as well as defensive magic when negativity is directed toward you.
Onyx will also help you gain emotional balance and self-control, when added to the benefit that it also balances the male and female polarities within each person, this is quite a powerful stone to have in your divination rituals, whether for protection or otherwise.

Zodiac

Associations: Saturn, Earth
Mystical Birthstone for the Month of December, and birthstone of most ancient cultures for the month of July.
Stone of Capricorn for a positive influence, and Leo, to dream of onyx signifies a happy life with a suitable companion.

Chakra Classification

Onyx is associated primarily with the 1st, or Root/Base Chakra,. It assists with challenges in life, especially those caused by a drain of energy. It prevents the draining away of personal energy and can be used for protection from such. It also helps with grounding and controlling or eliminating excess or unwanted energies.
Black onyx and red onyx are associated with the 1st, or Root/Base Chakra,. White onyx is associated with linking the 1st, or Root/Base Chakra, and 7th, or Crown Chakra to have balanced energy throughout the chakra system. Excellent for centering and aligning your full being with higher powers.

Translucence

Onyx is a translucent stone; if you hold a piece of it up to the light, you can see shapes and shadows through it. Because of this translucency, your setting material may show through or may affect the color of the stone. To avoid these problems, always use a white, latex modified thin-set mortar. The white mortar will avoid any discoloration of the onyx once it is installed, and will help preserve its translucency. Once the mortar has been keyed, or grooved, to the correct depth, smooth out the grooves with the edge of the trowel. This will prevent the grooves from producing shadows that my be seen through the stone after installation.

Fragility

Because onyx is one of the most fragile natural stones, it is frequently produced with a mesh, resin or fiberglass backing to help give it strength as a tile. This backing can make it more difficult to cut; always use a wet saw with a diamond blade to help cut the material cleanly. Because onyx is so fragile, it may crack if it is placed on an unstable or uneven substrate. Always make sure the substrate is strong and level before installation. A 5/8-inch cement backerboard is recommended beneath onyx tiles in a floor installation, while 1/4-inch cement backerboard is recommended beneath a wall tile installation.

Variability

No two pieces of onyx tile will ever look completely the same. Onyx may vary tremendously from piece to piece and within one piece. Within one lot, it is not uncommon to find pieces of onyx that are completely different colors from one another. To ensure a pleasing layout of the tiles and prevent the colors from clumping or grouping, do a dry layout of the tiles before installing them. Take pieces of onyx from all of your boxes to thoroughly blend them and mix up the colors so that the variation is well represented throughout the entire installation.

Sealing

In addition to being fragile, onyx is also extremely porous. It will absorb moisture and is extremely susceptible to both etching and stains. To protect the stone, seal it well with an impregnating sealer meant for porous stones prior to grouting it. The sealer will help as a grout release to make clean up easier, while it helps to protect the stone from future staining. When onyx is well-sealed, water should bead up on its surface as it does on a waxed car. When the stone stops doing this, it should be re-sealed with another coat of impregnating seale.