Collection: Onyx

What Is Onyx?

Onyx is banded chalcedony, a fine-grained quartz, with its bands running straight and parallel; when the bands are red-brown and white it is sardonyx. The name comes from the Greek word for fingernail or claw, for the pale streaks that run through it, and the Romans loved it for cameos and seals because a carver could cut a white figure standing on a black ground from a single stone. It is 6.5 to 7 on the Mohs scale, takes a mirror polish, and is safe in water.

Two honest notes, because the word onyx is stretched in the stone trade. First, nearly all the solid black onyx sold today, including ours, is chalcedony or agate darkened by the sugar-and-acid method that Pliny described two thousand years ago; the stone is real, the even black is helped. Second, the green and blue onyx of bowls, points, lamps, and many tumbles is not chalcedony at all but banded calcite, sold as onyx marble since antiquity. It is softer, about 3 on the Mohs scale, it scratches and fizzes in vinegar, and it is beautiful in its own right. Our listings say which is which, and our blue onyx tumbles are marked as heat treated.

Black Onyx Meaning

In crystal practice black onyx is the stone of steadiness and protection. Scott Cunningham lists onyx as projective, ruled by Mars and Fire, and used for protection and defensive magic, and the folk use has hardly changed: a piece at the threshold, a bracelet on the wrist through a hard stretch, a worry stone in the pocket for a steady hand. It is a root chakra stone in the modern system, worn for grounding and for the self-control the old lapidaries promised. The full lore, the zodiac, and the difference from black tourmaline are on our black onyx meaning page and in our comparison of black tourmaline and onyx. Green onyx carries the heart-stone lore of green calcite, calm and forgiveness, and blue onyx is worn at the throat for the same calm speech as any blue stone.

What You'll Find Here

Black onyx stones. Tumbled black onyx by the pound for grids, jars, pouches, and the doorway, and polished worry stones for the pocket.

Onyx bracelets. Black onyx beads in 4 millimeter and 8 millimeter sizes, black onyx alternated with ruby zoisite, and the seven chakra bracelets that use black onyx as the grounding spacer bead.

Green and blue onyx. Green onyx and heat-treated blue onyx tumbled stones by the pound, striped onyx tumbles, a green onyx polished point, and a green onyx lamp lit from within so the bands show.

Onyx tools for the altar. Onyx mortar and pestle sets for grinding herbs and resins, onyx offering bowls, and onyx rune sets in black and blue when they are in stock.

Carved stone beads. Heart, frog, and turtle beads in assorted stones, onyx among them, for stringing and for the altar dish.

How to Use Onyx

Practitioners keep black onyx by the door and on the sill for protection, wear it on the left wrist for steadiness coming in, and carry a worry stone through the meeting or the hard call. It grounds a grid built for protection, sits at the root position in a chakra layout, and stays in the pocket through a season that needs nerve. A green onyx bowl holds salt or offerings on the altar, and an onyx mortar grinds resin cold and clean. Cleanse black onyx with water, smoke, sound, or a night on selenite; it is hard enough for all of them. Keep green and blue onyx away from vinegar, lemon, and salt water, which etch calcite, and wipe them with a soft damp cloth instead.

Explore Related Collections

Onyx sits with the other black protectors, black tourmaline, black obsidian, hematite, and jet, all gathered under protection crystals and root chakra crystals. For the whole shelf of black stones and how they differ, read our protection crystals guide. The onyx mortars are also in mortar and pestle sets, and the rune sets in rune stones.

Frequently Asked Questions

What is onyx stone?
Onyx is banded chalcedony, a fine-grained quartz with straight parallel bands, 6.5 to 7 on the Mohs scale. Most solid black onyx sold today is chalcedony or agate darkened by a sugar-and-acid treatment known since Roman times, and green and blue onyx are banded calcite, a softer stone sold as onyx marble.

Is black onyx natural?
The stone is natural chalcedony or agate; the even black color is usually helped by the sugar-and-acid method Pliny described two thousand years ago. Our listings say so, and the treatment does not change how the stone is used.

What is black onyx good for?
In crystal practice, protection and steadiness. Cunningham lists it under Mars and Fire for protection and defensive magic, and practitioners keep it at the door, wear it as a bracelet, and carry it as a worry stone. It is a root chakra stone for grounding.

What is the difference between onyx and black tourmaline?
Onyx is banded quartz with an even, glassy black polish and is usually dyed. Black tourmaline is a different mineral that grows in striated rods, is never dyed, and looks matte and ridged in its raw form. Both are protection stones in the lore; our comparison guide covers the rest.

Is green onyx real onyx?
Green onyx is banded calcite, also called onyx marble, not the quartz onyx. It is real stone with the same layered look, but softer, so keep it away from acids and salt water. Our listings say which pieces are calcite.

Can onyx go in water?
Black onyx, yes: it is hard quartz and rinses safely. Green and blue onyx are calcite and should only be wiped with a damp cloth, never soaked or cleaned with vinegar or lemon.