triclinic Simulant turquoise simulant
Gilson Turquoise (Cabochon)
CuAl6(PO4)4(OH)8*4H2O
Crystal Structure
#! Species: Gilson Turquoise
#! System: Triclinic (-1)
#! Habit: Triclinic pinacoidal crystal habit
triclinic[-1]:{010}@1.0 + {001}@0.9 + {110}@0.7
triclinic
-1
{010} {001} {110}
Quick Facts
Hardness
5.0
Specific Gravity
2.4
Refractive Index
1.6
Optical Character
Biaxial +
Physical Properties
Crystal Systemtriclinic
Hardness (Mohs)5.0
Specific Gravity2.4
LustreWaxy to dull
Optical Properties
Refractive Index1.6
Birefringence0.04
Optical CharacterBiaxial +
FluorescenceInert to weak greenish
Origin & Identification
OriginSimulant
Growth MethodGilson
ManufacturerGilson
First Produced1972
Diagnostic FeaturesMore porous than natural, lower SG (2.4 vs 2.6-2.8), distinctive blue appearance under magnification (lacks natural matrix patterns), may absorb dye unevenly, spiderweb pattern may appear too regular
Colours
BlueGreenish-bluewith optional dark matrix
Common Inclusions
Regular porosity patternAbsence of natural matrix
Natural Counterpart
The natural gem this simulant imitates
Related Minerals
Other minerals in the triclinic system
