Gemmological formulas

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  1. What is the chemical formula of emerald?
    Be3Al2(SiO3)6
  2. What is the crystal system of emerald
    Hexagonal
  3. What is the SG of emerald?
    2.76 on average
  4. What is the refractive index of emerald?

    What is the birefringence factor of emerald?
    • nω = 1.564–1.595
    • nε = 1.568–1.602

    δ = 0.0040–0.0070
  5. Definition of Acicular
    Needle-like crystal habit
Author:
katkoutakis
ID:
64684
Card Set:
Gemmological formulas
Updated:
2011-02-07 21:02:40
Tags:
Emerald
Folders:

Description:
Green variety of beryl
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