A yellow-red to red-brown gem variety of zircon.
General Information
A variety or type of:Zircon
Chemical Formula
Michael O’Donoghue, Gems, Sixth Edition (2006)
Photos of natural/un-cut material from mindat.org
Physical Properties of Hyacinth
Mohs Hardness6.5 to 7.5
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
Specific Gravity3.93 to 4.73
Walter Schumann, Gemstones of the world (2001)
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
Cleavage QualityIndistinct
Walter Schumann, Gemstones of the world (2001)
Arthur Thomas, Gemstones (2009)
Optical Properties of Hyacinth
Refractive Index1.810 to 2.024
Walter Schumann, Gemstones of the world (2001)
Walter Schumann, Gemstones of the world (2001)
Colour (General)Yellow, yellow-red, yellow-brown
Management Team, Gemdat.org (2012)
Arthur Thomas, Gemstones (2009)
Further Information
Mineral information:Hyacinth information at mindat.org
Significant Gem Localities
Sri Lanka
  • Sabaragamuwa Province
    • Ratnapura District
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