Alexandrite
Complete dossier & evidence
The same stone, a different illumination—and a story with gaps.
Material identity
Chrysoberyl · BeAl₂O₄ · Mohs 8.5
Urals, around 1830; no single finder established here
GIA places the early discovery in the Ural Mountains around 1830. This source set does not securely establish one individual first finder. The namesake, later scientific work and romantic birthday tales are not interchangeable discovery evidence.
Keep the date—and keep the uncertainty.
GIA places alexandrite's early discovery in Russia's Ural Mountains around 1830. Its name is associated with the future Alexander II. A royal namesake gives the story context, but does not identify the person who first noticed the stone or prove every repeated account about the exact day.
Rather than smoothing those gaps into a dramatic scene, the atlas keeps the claim narrow. The location and approximate period are supported; a single first-finder identity is not established by the cited material. A responsible history can still be vivid: the puzzle is how one material appears so different under changing illumination, and how people recognised that behaviour.
Chrysoberyl is not beryl.
Alexandrite is a colour-change variety of chrysoberyl. Despite the similar sound of the names, chrysoberyl and beryl are different minerals; emerald belongs to beryl, not to the same mineral family as alexandrite.
That distinction matters when an expression such as emerald by day and ruby by night is used. It is a colourful analogy for appearance, not a statement that the stone changes into those two minerals. The composition does not switch when the lamp does. Use the family and formula first, then explain why the interaction of light and material produces a different visual impression.
Change the lamp, not the gemstone.
Alexandrite's characteristic colour change is associated with how the material absorbs light and with the spectral balance of the illumination. It can appear greener under daylight-like conditions and redder under incandescent illumination, with considerable variation between specimens.
This is not the same as simply turning a pleochroic crystal. Both effects can be relevant to gem observation, but the defining comparison here changes the light source. A pair of photographs should therefore report the lighting conditions. The side-by-side image in this atlas is a real photographic pair from its source record—not a green stone repainted red by the interface.
A Russian beginning is not a universal origin.
Russia's historical importance should not become a rule that all natural alexandrite must be Russian. GIA discusses later sources including Sri Lanka, Brazil and East Africa. The Smithsonian also records examples from Russia and Sri Lanka in its collection.
The map identifies selected source regions without drawing an invented trading route. An old Russian object and a newer Brazilian specimen have separate histories. No amount of resemblance in a colour-change photograph can establish that they share a mine. A colour, a mineral identity and a geographic-origin opinion are different claims and need different evidence.
The most useful photograph shows its conditions.
David Weinberg's documented photographic pair shows a cushion-cut alexandrite described as 26.75 carats under daylight and incandescent light. The value of the image is the controlled comparison described by the record, not an invitation to assign the pictured specimen's weight or quality to another stone.
A second rough-crystal photograph has its own locality and light labels. Those exact labels are retained rather than silently changed to fit a standard story. The museum collection link offers additional named specimens, but inconsistent weights in a source's prose and table are not repeated as settled measurements here. A precise caption is part of the evidence, not decoration beneath it.
alexandrite-collection photo-alexandrite-pair photo-alexandrite-rough
How strong is the change—and what does that mean?
Two appealing colour names do not capture every aspect of a colour-change stone. The actual hues, their tone and saturation, the strength of the change, lighting conditions and the quality of the cut all affect what a viewer experiences. A photograph can compress or exaggerate some of those differences.
The cabinet therefore labels the variable being discussed rather than scoring a stone. A green swatch and a purple-red swatch show categories; they are not proof of a one-hundred-percent change, a grade or a natural origin. For a personal gem, request a description based on appropriate examination and compare it under the conditions the record actually specifies.
A good hardness number still needs context.
Alexandrite has a Mohs hardness of 8.5 and generally good toughness. GIA's care guidance nevertheless requires attention to treatments and surface-reaching fractures, as well as the condition of the complete jewel. Strong material is not permission to ignore a loose setting.
Keep the practical sequence simple: identify the gem, read treatment information, inspect condition and only then choose cleaning and wear guidance. A website can explain the reasoning but cannot inspect the item on your hand. This is particularly important for pieces with several materials, where the most vulnerable component may not be the central gemstone.
A story can stay magical without claiming magic.
The surprise of two appearances is enough. There is no need to say the gem has transformed into another mineral, to manufacture a prince's discovery scene or to promise that a viewer can identify a natural specimen from colour change alone.
For an enthusiast's review, record the source of the photographs and the light conditions first. Then describe the visual change and the cut's character, keeping observation apart from authentication. End with what would require direct examination. This gives the visitor a practical way to understand a fascinating stone while preserving the honesty of both the history and the technical explanation.
Places & dates: timeline
Early Ural discovery
Around 1830
The regional and approximate-date claim is stronger than a single first-finder claim in this source set.
A royal namesake
19th-century naming
The name refers to the future Alexander II; a namesake is not necessarily the finder.
Beyond Russia
Later source history; no single date assigned
Sri Lanka, Brazil and East Africa broaden the source story.
A documented two-light comparison
2006 published image record
The source describes the pictured 26.75-carat stone in daylight and incandescent illumination.
Geographic evidence
Ural Mountains, Russia
discovery
Approximate regional location for the early nineteenth-century discovery.
Approximate region or city marker, not an exact extraction site.
Approximate coordinates: 57.0, 60.6
Sri Lanka
source
A later source context and locality of museum examples.
Approximate region or city marker, not an exact extraction site.
Approximate coordinates: 7.5, 80.7
Brazil
source
Selected later source region, not a verified mine for every photograph.
Approximate region or city marker, not an exact extraction site.
Approximate coordinates: -19.5, -41.6
Washington, DC
object
A collection location for documented Russian and Sri Lankan specimens.
Approximate region or city marker, not an exact extraction site.
Approximate coordinates: 38.89, -77.03
Colour explanations
Daylight-like green
Green to bluish-green is one side of the familiar comparison, with variation between specimens.
Illustrative swatch, not a calibrated sample or grade.
Incandescent reddish-purple
A different light source can produce a redder appearance in the same material. That is not a change into ruby.
Illustrative swatch, not a calibrated sample or grade.
Intermediate appearance
Mixed illumination and individual variation complicate a simple two-colour slogan. No percentage-change grade is assigned by this display.
Illustrative swatch, not a calibrated sample or grade.
Photographs & rights
Alexandrite under two light sources
Responsive WebP copy · full frame retained
Responsive display copies: proportionally downsampled and encoded as WebP by Goutte de Rosée; full frame retained, with no crop, retouching, recolouring or enlargement. Display orientation follows the original EXIF; any colour profile and attribution metadata are retained. The original-file description above remains applicable to the preserved original.
David Weinberg / Alexandrite.net · CC BY-SA 3.0
Item-level licence or public-domain statement in the cited source record. Keep attribution and applicable share-alike terms.
No colour changes. Reference UI fits the complete image; CSS display resizing only.
Self-hosted original photograph. No crop, retouch, upscaling or recolouring.
Photograph source record
Brazilian alexandrite crystal, two views
Vzb83 · CC BY-SA 2.5
Item-level licence or public-domain statement in the cited source record. Keep attribution and applicable share-alike terms.
No colour changes. Reference UI fits the complete image; CSS display resizing only.
Photograph unavailable locally. HTTP Error 429: Too many requests - please contact noc@wikimedia.org to discuss a less disruptive approach or instead use thumbnail images in sizes listed on https://w.wiki/GHai. (0c640b1)
Photograph source record
Questions to keep
- What actual illumination produced each photograph?
- Is a namesake being mistaken for the discoverer?
- Which claims require direct gemological examination rather than a colour comparison?
Source register
Alexandrite: History and lore
History and lore; beliefs reported in history sections are not scientific claims.
Alexandrite: Material description
Material description; beliefs reported in history sections are not scientific claims.
Alexandrite: Care and cleaning
Care and cleaning; beliefs reported in history sections are not scientific claims.
More than the Mohs scale: gem durability
Scratch resistance, toughness and stability are different properties.
Alexandrites in the National Gem Collection
Russian and Sri Lankan examples and colour behaviour; conflicting table/prose weights deliberately omitted.
Alexandrite: gem encyclopedia
Colour-change chrysoberyl and material identity.
Natural Earth terms of use
Public-domain map base. Pins are our approximate editorial region indicators, not mine survey coordinates.
Alexandrite under two light sources — photograph record
A 26.75-carat cushion-cut alexandrite shown in daylight and incandescent light in the source record. This is a photographic pair, not an interface recolouring. Licence: CC BY-SA 3.0
Brazilian alexandrite crystal, two views — photograph record
Brazilian alexandrite crystal. The source labels the left image daylight and the right fluorescent light; those labels are retained without silently substituting incandescent. Licence: CC BY-SA 2.5