amorphous Inosilicates
Jadeite (Massive (gem-quality))
Formula NaAlSi2O6
Crystal Structure
#! Species: Jadeite
#! System: Monoclinic (2/m)
#! Habit: Massive interlocking aggregate (gem quality)
amorphous[cryptocrystalline]:{massive}
amorphous
2/m
{massive}
Quick Facts
Hardness
6.5
Specific Gravity
3.25
Refractive Index
1.654
Optical Character
Biaxial +
Physical Properties
- Crystal System
- amorphous
- Hardness (Mohs)
- 6.5
- Specific Gravity
- 3.25
- Cleavage
- Good {110} at ~87°
- Fracture
- Splintery (tough due to interlocking fibrous texture)
- Lustre
- Vitreous to greasy
Optical Properties
- Refractive Index
- 1.654
- Birefringence
- 0.013
- Optical Character
- Biaxial +
- Dispersion
- 0.012
Characteristics
Colours
Imperial greenLavenderWhiteYellowOrangeBlack
Localities
Myanmar (Burma)GuatemalaJapanRussiaUSA (California)
Common Inclusions
Fibrous interlocking textureBlack chromite spots (in green)Fracture fillings
Known Treatments
Polymer impregnation (B jade)Dyeing (C jade)Wax treatment (traditional)
Crystal Forms
massive
Diagnostic Features
Interlocking granular texture; high toughness; higher SG and RI than nephrite; absorption at 437nm
Related Minerals
Other minerals in the amorphous system
Ambroid (Pressed Amber)
Compressed and fused amber chips (same chemical composition as amber — fossil resin; succinite for Baltic amber)
Bone (Ivory Simulant)
Ca5(PO4)3(OH) (hydroxyapatite; same general composition as ivory dentine) in collagen matrix; technically microcrystalline hydroxyapatite but gemologically treated as amorphous/aggregate biomineral
Chalcedony (Botryoidal)
SiO2
Chalcedony (Massive)
SiO2
Chrysocolla
(Cu,Al)2H2Si2O5(OH)4.nH2O
Copal (Amber Simulant)
Partially polymerised plant resin (labdanoid diterpenes; younger resin; not fully matured/polymerised)