Crystal System: Tetragonal.
Cell salt: Zirconium silicate, often with some hafnium.
Colour: Grey, brown and green; transparent red (Hyacinth); and colourless or smoky (Jargoon).
Element: Fire and earth.
Planet/sign: Mars/Aries; Saturn/Capricorn.
Uses: This stone helps us synthesize our action so that we become focused to accomplish our goals.