Chalcedony is a cryptocrystalline form of silica, composed of very fine intergrowths of quartz and moganite. These are both silica minerals, but they differ in that quartz has a trigonal crystal structure, while moganite is monoclinic. Chalcedony’s standard chemical structure (based on the chemical structure of quartz) is SiO2 (silicon dioxide).
Chalcedony has a waxy luster and may be semitransparent or translucent. It can assume a wide range of colors, but those most commonly seen are white to gray, grayish-blue or a shade of brown ranging from pale to nearly black. The color of chalcedony sold commercially is often enhanced by dyeing or heating.
The name chalcedony comes from the Latin chalcedonius (alternatively spelled calchedonius) and is probably derived from the town of Chalcedon in Asia Minor. The name appears in Pliny the Elder’s Naturalis Historia as a term for a translucid kind of jaspis. Another reference to a gem by the name of khalkedon (χαλκηδών) is found in the Book of Revelation (21:19); however, it is a hapax legomenon found nowhere else in the Bible, so it is hard to tell whether the precious gem mentioned in Revelation is the same as the mineral known by this name today.
Characteristics of Chalcedony
- Hardness: 6 – 7
- Transparency: Translucent to opaque
History of Chalcedony
Our ancestors treasured chalcedony. It may not be the most eye-catching of the semi-precious gems available, but it does have one very special property: it’s perfect for carving into. In Minoan Crete in the Bronze Age at the Palace of Knossos, our Minoan predecessors were carving designs into the stone to create official seals. In fact, chalcedony seals have been discovered which date back to 1800BC. Chalcedony is the perfect material to make a seal from as wax does not stick to this special stone.
A little later in history, carved chalcedony rings, created as part of beautiful intaglio designs have been found right along the trade routes of Central Asia. Whilst in ancient, 1st Century AD Afghanistan the gem was used to create all manner of items from traditional seals to knives.
There is historic mention of Chalcedony in religion too. The Jewish High Priest’s Breastplate worn by Aaron, the brother of Moses, is said to have been decorated with 12 inscribed gems describing the 12 tribes of Israel.
We owe the name ‘chalcedony’ to the Ancient Greeks. Though there is no strong evidence, it is widely accepted that the stone is named after the Greek town of Chalcedon in Asia Minor. The Latin form of the word ‘chalcedonius’ appears in Pliny the Elder’s Naturalis Historia and refers to a form of Jaspid.
The great Roman orator Cicero was said to wear a blue chalcedony around his neck as the stone is said to be of particular benefit to public speakers. Known as the ‘speaker’s stone’ the gem is said to help those who must measure their words, particularly lawyers and actors.
Meaning of Chalcedony
Chalcedony is a nurturing stone that promotes brotherhood and good will. It absorbs negative energy. It brings the mind, body, emotions and spirit into harmony. Chalcedony instills feelings of benevolence and generosity. It alleviates hostility and transforms melancholy into joy. Eases self-doubt. Creates openness and enthusiasm. Absorbs and dissipates negative thoughts, emotions and bad dreams.
Chalcedony improves mineral assimilation and combats mineral buildup in veins. Lessens the effects of dementia and senility. It increases physical energy. Heals the eyes, gallbladder, bones, spleen, blood and circulatory system.
Perhaps because of it’s ‘clean’, milky and soothing appearance, chalcedony has been said to have many health benefits and healing properties over the centuries.
Associated with the fifth or ‘throat’ chakra, many new age healers believe that is has particular benefits for sore throats and throat infections. As the throat is at the core of how we communicate, chalcedony is thought to be of help with communicating ideas, feelings and beliefs – restoring balance throughout the body.
The stone is also said to promote lactation in breastfeeding mothers, alleviate the effects of plant-based allergies, reduce edema, reduce glaucoma and aid the treatment of dementia and Alzheimer’s.
There are lots of superstitions surrounding chalcedony which accompany its supposed health benefits. Thought to help with self-doubt, this soothing, calming stone is said to be of special help to those who are plagued by anxiety, constant worries, and irrational bursts of anger.
For the spiritual amongst us, chalcedony is thought to be a powerful conduit between our realm and more spiritual realms, aiding communication with spheres other than our own and encouraging telepathy or past life remembrance.
Chalcedony