Properties
Mineral group: Chrysoberyl
Chemistry: BeAL2O4
Color: Golden-yellow, green-yellow, green, brown, red
Crystal system: Ortorombic
Mohs Scale hardness: 8,5
Refractive index: 1.746-1,763
Birefringence: 0.007 - .011
Specific gravity: 3,70-3,78
Information
Can be confused with
Synthetic sapphire, synthetic spinel, andalusite and garnet pyrop. There is also synthetic alexandrite although color change sapphire is more commonly used as it is cheaper.
Treatments
Normally alexandrite is un untreated. Even though attempts have been made it doesn't appear possible to enhance the color change effect with heat treatment.
Oil is sometimes used to hide fractures.
Instruments for identification
Microscope/Loupe can reveal the possible inclusions.
Chealsea filter can be used as the alexandrite color shows up as red due to its chrome content.
The color change effect is the main effect to ascertain. No color change - no alexandrite. The color change can be observed from daylight to build light (not LED).
Known deposits
Found for the first time in the Urals and named after Tsar Alexander II. The Russian deposits are er however exhausted and presently the largest deposits are found in Sri Lanka, Zimbabwe and Brasil. Burma, Madagascar and Tanzania also have deposits of significance.
Miscellaneous
By far the largest alexandriet has been found in Sri Lanka in 1876. The largest cut stone weighed 66 carat and can be seen at the Smithonian Institute.
Gemstone Guides & Knowledge
Read more about Alexandrite (Chrysoberyl) on RIDDGEM Blog
Watch movies and Shorts about Alexandrite (Chrysoberyl) on RIDDGEM YouTube
Read/learn more about Alexandrite
Alexandrite in healing (Source: ChatGPT)
Alexandrite is an unusual and fascinating crystal known for its color-changing property, which is said to reflect its unique healing properties. In crystal healing, alexandrite is associated with transformation, balance and inner strength.
Read/Learn more about Alexandrite Healing Properties
