Chalcedony
Also Blue chalcedony, Calcedonius
Translucent and waxy: milk white, pale grey or soft blue-grey, sometimes faintly banded. The look is half-lit rather than glassy.
- Crystal system
- Trigonal
- Hardness
- 6.5-7 Mohs
- Handling
- Durable and safe in water. Much blue chalcedony and nearly all bright agate on sale is dyed, and dye can fade in sunlight or leach out in bleach and solvent, so wash a dyed piece in plain cool water only and keep it out of the sun.
- In water
- Safe
What it is held to be for
Chalcedony is quartz grown too fine to see, which gives it a waxy, half-lit look. It is the parent of agate, carnelian and onyx, but the pale grey-blue kind is its own stone. Roman seal-cutters favoured it because it takes a crisp intaglio and does not stick to warm wax. The lapidaries give it to speech, and to people who must say the same thing patiently many times over.
Marbode of Rennes, De lapidibus (calcedonius)
Correspondences
These are the tradition's ascriptions, not properties of the mineral.
- Planet
- Moon, Mercury
- Element
- Water
- Signs
- Cancer, Gemini
- Chinese phase
- Metal
- Year animal
- Monkey, Ox
- Centre
- Throat Vishuddha
- Sephirah
- Yesod
How it is used
Worn at the throat, or carried by anyone who talks for a living: teaching, nursing, care work, complaints. Traditionally kept by nursing mothers and by people who must repeat themselves without hardening.
Today
Hold the chalcedony while you say, in a level voice, the thing you have already said five times, a sixth time.
A longer working
At the end of a day of talking, run the chalcedony under a cool tap and dry it. Then sit and say aloud, to nobody, the three sentences you were sick of by four o'clock. Say each one once, slowly, and let it go. Set the stone by the door ready for the morning. The old lapidaries have it worn pierced on a cord; a coat pocket does as well.
Works with
- Herb
- Lemon balm
- Incense
- Mastic