what''s the difference between alexandrite and color change garnet?

[donnanwl]

I feel color change gem are very interesting, but what''s the difference between alexandrite and color change garnet?

 

[Gemmal]

Great question. I often wondered that myself. I hope someone does answer this as I LOVE alexandrites. All I know is one is Waaaaay more expensive.

 

[JulieN]

succinct post by Josh https://www.pricescope.com/community/threads/alexandrite-learn-about-this-color-change-gem.9782/=

 

[RockDoc]

Date: 7/25/2006 3:35:26 AM
Author:donnanwl
I feel color change gem are very interesting, but what''s the difference between alexandrite and color change garnet?

Each gem is classified with its own name based on its crystal structure, chemical make up, specific gravity, color, refractive index, hardness and more.

Each stone gets its mineral name base on the above.

Alexandrite is the color change variety of Chrysoberyl.

Garnet is the mineral name for a wide "family" of stones. Just to list some of the varieties. Almandite, Grossularite, Rhodolite, Spessartite, Andradite and more. Some of the different ones above also have other names based on their colors and varying minerological characteritics. A sub variety of Andradite Garnet is Demantoid Garnet. These are rather uncommon and are green in color with a unique type of inclusion called a "horsetail".

Any of these varieties of garnet can exhibit color change.

There are other color change stones as well.

Just some that occasionally have this property are.

Diamond
Sapphire
Spinel
Tourmaline
Sugilite/Lavullite
Garnet
and of course Alexandrite

Hope this helps.

Rockdoc

 

[donnanwl]

Rockdoc, it really helps, thank you.

Than, may we classified them from a simple consumer point? which group is more rare, or i should say, has the potential for the value increasing?

And, i specially love the color change from green to red, which group has that combination?

Thanks a lot!

 

[Richard M.]

Date: 7/25/2006 10:06:54 AM
Author: RockDoc
Any of these varieties of garnet can exhibit color change.

I''ve made a special study of garnet, especially color change, and the color-changing garnets in today''s commercial market are all mixtures of pyrope and spessartine. It makes no difference whether they''re from Tanzania, Kenya, Madagascar or Sri Lanka.

Some rare demantoids (andradites) exhibit color change as do some almandines from Idaho. The claimed color change in the almandines is truly more of a color-shift of the same hue based on personal observation.

I''ve done a pretty wide literature search and that''s all I''ve found. I''d be very interested in any citations you have for color changing properties in other garnet species. It''s certainly possible given garnets'' propensity for isomorphous replacement, miscibility and wide variation in trace element content.