Back to the Twelve Stones
Foundation 12 of 12
Revelation 21:20
Amethyst
ἀμέθυστοςThe last foundation is quartz that keeps time: piezoelectric, it sets the frequency in modern oscillators and clocks.
Mineralogy
- Greek name
- amethystos (ἀμέθυστος)
- Modern identification
- Quartz (var. Amethyst)
- Chemical formula
- SiO₂
- Crystal system
- Trigonal
- Optical class
- Uniaxial (+)
- Birefringence (Δn)
- 0.009
- Refractive indices
- 1.544–1.553
- Color / appearance
- Purple (Fe³⁺ irradiation)
Piezoelectric; used in modern oscillators and frequency standards.
The light between
Amethyst is anisotropic: enter it with a single ray of light and it leaves as two, split apart by the crystal's inner order. This is birefringence, the same property shared by every one of the twelve foundation stones, and by none of the cubic stones left out of the list.
In the high-priestly breastplate of Exodus 28, this position held Onyx in the Septuagint reckoning.
Hold the light in your hand
The Revelation Stones collection brings each foundation stone into the room with you, and the Light Between research explains what you are looking at.