Accessibility options

Switch to preferred accessibility theme:


Increase or decrease the text size:

  • Internet Explorer: View > Text Size > Largest

Keyboard navigation and access keys:

  • A - Accessibility options
  • 0 - Skip navigation
  • 1 - Home
  • 2 - Alexandrite chapters
  • 3 - Alexandrite directory
  • 4 - Alexandrite forums
  • 5 - Alexandrite gemstones
  • 6 - Alexandrite localities
  • 7 - Contact information
  • 8 - About Alexandrite Guide
  • 9 - Sitemap
  • Press ALT + Access Key, then ENTER.

Close

Alexandrite

Tsarstone collectors guide

Alexandrite guide forums

Page 1 of 1 50 results per page
Sort by: Most recent last
I want to know more about colour change garnets. From all the comments I have read, I understood that the colour change in garnet is supposed to occur between morning and late afternoon light, which is not the same as with alexandrite color change phenomena which cause colour change depending on daylight and incandescent light. Does it mean that garnets will not change colour under an incandescent light bulb?

What causes the garnet colour change? Is it the alexandrite effect or some other optical phenomena, like the Usambara effect for colour changing tourmalines?

I saw brown to red and greenish to reddish colour change. But garnets come in all kind of colours - pink, red, purple, orange, yellow, violet, green and even colourless. What kind of other colour change in garnets exist?
Faceted alexandrites and color change garnets can occur in wide range of colors that are a function of chemistry and crystallographic orientation, it is impossible to describe color change in anything but generalized terms.

However, our experiences photographing and grading both kinds of stones in a variety of light conditions suggest that color change garnet is usually more sensitive to color changes in the higher ranges of daylight above 4500 K. Whether in morning or afternoon daylight and with or without sunlight, alexandrite color is fairly constant and only shows a dramatic change under incandescent light.

color change garnet_zcg1006ah.jpg

Color change garnets on the other hand, often show a significant change between 4500K daylight and 6500K cool daylight (fluorescent light). Indeed some of the color change garnets especially from the new deposit in Chavia, Kenya have been referred to has tri color garnets because of their larger color change range. To appreciate the full range of colors in these stones we need to view them under incandescent, natural daylight, and fluorescent light. Without viewing the stones under every kind of light it will impossible to appreciate the full range of colors.

Attachment (s)

But what causes the garnet colour change - is it the alexandrite effect? For instrance - malaia garnet, malaya garnet and color change garnet are all a mixture of pyrope and spessartite so what's the difference? Why malaia garnet doesn't change colour?
Malaia is name given to garnets orange to pinkish orange to red in color which do not match the color and gemological properties of any of the other more well known varieties of garnet. (Some authors spell it Malaya garnet).

malaya_zmg120ac.jpg

Indeed, the word malaia means prostitute or out of the family in Swahili. Primarily composed of spessartite
and pyrope, the color and gemological properties occur in a range which can overlap with grossularite, rhodolite, and pyrope.

spessartite_yse246aa.jpg

Some of them may change color under daylight and incandescent lighting and these stones are more commonly and collectively known as Color Change Garnets. It is thought that the color change is due to the presence of vanadium or chromium in trace amounts. Our own observations indicate that color change could also be influenced by the needle like inclusions of rutile or actinolite which are common in the color changing stones but less apparent in the stones that don’t change color.

Attachment (s)

Topic page 1 of 1
1
Looking for a alexandrite
Hello, I've noticed that most of your alexandrites are from multicolour.com. Some time ago I've seen one alexandrite there, I saved a...
www.alexandrite.net/discussion/topic/looking-for-a-alexandrite-FRM-133
Cymophane or Cats eye?
What is the correct name and why?
www.alexandrite.net/discussion/topic/cymophane-or-cats-eye-FRM-164
Step Cut Alexandrite Oval, 2.6 cts
http://www.alexandrite.net/viewpage.html?id=ALX-001-00026
www.alexandrite.net/discussion/topic/step-cut-alexandrite-oval-2-6-cts-FRM-165
Step Cut Alexandrite Oval, 3.03 cts
http://www.alexandrite.net/viewpage.html?id=ALX-001-00023
www.alexandrite.net/discussion/topic/step-cut-alexandrite-oval-3-03-cts-FRM-166
Grading a color change gems?
How do you grade alexandrites ?
www.alexandrite.net/discussion/topic/grading-a-color-change-gems-FRM-167
Portuguese Cut Alexandrite Round, 1.19 cts
http://www.alexandrite.net/viewpage.html?id=ALX-001-00030
www.alexandrite.net/discussion/topic/portuguese-cut-alexandrite-round-1-19-cts-FRM-168
Step Cut Alexandrite Oval, 5.16 cts
http://www.alexandrite.net/viewpage.html?id=ALX-001-00003
www.alexandrite.net/discussion/topic/step-cut-alexandrite-oval-5-16-cts-FRM-169
Useful tool for beginners
Dedicated Alexandrite search
www.alexandrite.net/discussion/topic/useful-tool-for-beginners-FRM-172
Emerald Cut Alexandrite, 12.53 ct
Hi everyone! I recently (today!) got from my mom a really nice emerald cut Alexandrite. It was set in a ring she inherited and she wanted...
www.alexandrite.net/discussion/topic/emerald-cut-alexandrite-12-53-ct-FRM-173
What gemstones change color like alexandrite?
Several other well known gemstones, including diaspore, sapphire, garnet and spinel may also change color as a function of the light source
www.alexandrite.net/discussion/topic/what-gemstones-change-color-like-alexandrite-FRM-282
Colour changing Kunzite?
Does it mean that kunzite can change color?
www.alexandrite.net/discussion/topic/colour-changing-kunzite-FRM-336
Natural Alexandrite Pear 7.24 cts
Extremely rare Alexandrite (Chrysoberyl) Pear 7.24cts from Tanzania (Tunduru)
www.alexandrite.net/discussion/topic/natural-alexandrite-pear-7-24-cts-FRM-354
Browse gemstones tagged with color change gemstone
beautiful, but am looking for marquise cut
www.alexandrite.net/discussion/topic/browse-gemstones-tagged-with-color-change-gemstone-FRM-355
Alexandrite Specimens for collectors
I have 6 stones that I seem to be battling to get valued and i would like to sell. They are not cuttable as far as the jeweller is concerned...
www.alexandrite.net/discussion/topic/alexandrite-specimens-for-collectors-FRM-372
Alexandrite Specimens
I have 6 stones that I seem to be battling to get valued. They are not cuttable as far as the jeweller is concerned but could be good for...
www.alexandrite.net/discussion/topic/alexandrite-specimens-FRM-373
Alexandrite of Brésilia aproximatively 14 carats with another one half smaller of same crystal !!!
Hi everybody, I would like to know how much am lucky ?; My dead grandfather gave to me in succession a natural stone from Brésilia, and...
www.alexandrite.net/discussion/topic/alexandrite-of-brjsilia-aproximatively-14-carats-w-FRM-414
I was told this was an alexandrite when given to me.
changing colors are deep purple to redish pink, and Blue to Green.
www.alexandrite.net/discussion/topic/i-was-told-this-was-an-alexandrite-when-given-to-m-FRM-424

Tags

alexandrite purple alexandrite reference alexandrite book Karl Schmetzer Russian Alexandrites alexandrite reference book Karl Schmetzer color change color change gemstones color change garnet color change sapphire color change spinel garnet chatoyancy color change alexandrite jewelry alexandrite ring alexandrite mining alexandrite deposit african alexandrite Russian alexandrite natural alexandrite alexandrite appraisal alexandrite ring appraise color change garnets rhodolite Bekily Chavia malaia garnet garnet malaya garnet spessartites Spessartite tri color garnet tri colour garnet Chavia garnet color change gemstone gemstones alexandrite color synethic alexandrite acrylite gemstones valuation gemstone appraisal jewellery valuation jewellery appraisal award colour change stone Bekily garnet colour change garnets color change tourmaline Usambara effect Alexandrite Effect african alexandrite tanzanian alexandrite investment aelxandrite natural alexandrite russian alexandrite alexandrite specimen alexandite madagascar alexandrite alexandrite deposits pleochroism color fading kunzite kunzite pleochroism color changing gemstone alexandrite jewellery june birthstone alexandrite june birthstone colors june birthstone birthstone june gemstone natural alxandrite love tsarina ring alexandrite jewellery vintage alexandrite ring Art Deco alexandrite contemporary alexandrite ring bastnaesite bastnasite gemstone chrysoberyl synethic alexandrite alexandrite value appraiser color change diamond tavernier diamond purkinje shift purkinje effect created alexandrite lab created alexandrite alexandrite rough chrysoberyl rough acrylite chameleon plastic alexanrite alexandtrite mining alexandrite book Richard W. Wise Alexandrite Garnet blue color change garnet Richard Wise chrysoberyl rough chrysoberyl colour change stone color change kunzite Alexandrite Specimen synthetic alexandrite alexandrite engagement ring Paulo natural alexandrite ring eternity ring art deco alexandrite ring alexandrite mining blue peacock Novello mine alexandrite engagement ring Brazilian alexandrite color change gemstones malaya garnet Malaia garnet Colour change garnet alexandrite jewelry alexandrites gemstone june birthstone alexandrite pearl ring vintage alexandrite ring eternity ring yellow gold alexandrite ring mark henry alexandrite ring William Alxandrite marquise Bekily garnet alexandrite diamond ring natural alexandrite ring Zandrite appraisal jewelry valuation color change spinel color change sapphire color change garnet sapphire Novello Mine Girdlestone Farm Alexandrite Effect Usambara Effect Brazilian alexandrite gemological laboratories

Close options details