Is this consistent with alexandrite colour behaviour or is this a modified/corundum type situation?

[gt3ale]

Any help would be appreciated. It's difficult to capture the "correct" shades of these because they appear darker/lighter depending on which light and which angle but generally 2 stones are darker green vs lighter green for the other 2 in natural daylight. In candlelight there are some v dark tiny areas which appear red to scarlet but they are v tiny. The pinkpurple shade appears when I photograph under candlelight and if I play with the angles otherwise the stones dont appear this pink but I suspect that's my eyes because it was clear in the photo. The very dark sections can sometimes appear to be garnet red/brown or grey it just depends on the light and which angle you view it from. Just wanted to make sure this is consistent with alexandrite and not a modified sapphire or other artificially created chrysoberyl. Any help would be immensely appreciated!

 

[gt3ale]

Any help would be most appreciated

 

[gt3ale]

Someone just told me it looks like an amethyst! I have never seen an amethyst look green in daylight.

 

[Bron357]

Two other tests you can try yourself is a UV light. Alexandrite will glow a sort of orange colour, Amethyst won’t.
Another useful test is Specific Gravity. Look up a You Tube video on how to do this at home. Not too difficult but you do need accurate digital scales to .00 scale.
Using Specific gravity you can differentiate between gem types BUT remember that anything lab grown of the same chemical composition will have the same SG as natural from the earth.
Alexandrite is around 3.7 - 3.8
Quartz is around 2.65
Sapphire is around 3.97 - 4.08.
There other colour change gems ie Fluorite and garnet that can show a similar “green to purple red” colour change.

 

[pokerface]

Definitely not amethyst and pretty certainly not alexandrite. Whatever it is, it is not gem grade, and not anything of any value.

 

[Bron357]

As with all gemstones a large proportion of their “value” comes from their beauty and how close to being an “ideal example” of their type.
With Alexandrite the most important attribute is the colour change and it’s strength.
The ideal daylight colour is a deep but vivid teal green, changing to a rich Purple red under incandescent.
Origin is important if you have genuine Russian Alexandrite but realistically this is hard to substantiate. Most new finds comes from either Brazil (preferred as it is more like Russian material) or India. The Indian material tends to be toned to less favourable hues.
Often the “daylight colour” is more grey green or more yellow green - not as desirable.
Often the “incandescent colour” is a more murky brownish purple or orangish purple - not as desirable.
Then just as important is the strength of the change, not all Alexandrite show a strong change. The change can be too washed out / faint - not as desirable.
After that comes clarity. Alexandrite like Emerald is not expected to be “flawless” however if the gem stops being transparent the value drops significantly. Material that is translucent might be “cabbed” but material that is more opaque tends to be kept as a mineral specimen as it has no great value.

 

[Bron357]

These are Brazilian Alexandrite.

 

[Bron357]

This, from its inclusions, I believe is Russian Alexandrite.

 

[Gloria27]

Spodumene?
Hackmanite?

 

[pokerface]

I agree with the guess of hackmanite.

 

[gt3ale]

Two other tests you can try yourself is a UV light. Alexandrite will glow a sort of orange colour, Amethyst won’t.
Another useful test is Specific Gravity. Look up a You Tube video on how to do this at home. Not too difficult but you do need accurate digital scales to .00 scale.
Using Specific gravity you can differentiate between gem types BUT remember that anything lab grown of the same chemical composition will have the same SG as natural from the earth.
Alexandrite is around 3.7 - 3.8
Quartz is around 2.65
Sapphire is around 3.97 - 4.08.
There other colour change gems ie Fluorite and garnet that can show a similar “green to purple red” colour change.

Thank you. Under UV light this actually is a raspberry/magenta/pink red. I know they arent gem grade (I wanted rough bit's for the sentimental value I suppose). These are from russia, so we all know the deposits are well exhausted centuries ago. My guess is these may be just remaining rocks that remain because cannot be used by lapidaries. The RI is on the way and I didnt know about the gravity test will read up on it - thank you! I didnt know about fluorite and pre-snooze reading last night it seems the shift is more blue to red on fluorite? I havent been able to find a green to red like alexandrites? The dark red on the small roundish piece strikes me as garnet although it looks grey like anthracite in daylight. under candlelight it is the dark red brown of garnet. Could this possibly be a russian demantoid? I believe they came out of the same area/mines as the alex deposits of old.

 

[gt3ale]

These are Brazilian Alexandrite.

Thank you the visual helps a lot!

 

[gt3ale]

This, from its inclusions, I believe is Russian Alexandrite.

Ive seen rounds like this before. Lots of inclusions, but the shift was dark green to dark red/garnetlike or light green to light pink (I guess the shade that I attached in my candle photo initially). Do they normally turn to this shade of purple under candlelight?

 

[gt3ale]

Spodumene?
Hackmanite?

I have never heard of these. Will check!

 

[gt3ale]

I agree with the guess of hackmanite.

This looks like the 2 v light ones I have. But doesnt hackmanite retain some of the colour change when exposed to UV? Also I am finding more references to blue in daylight to the purple under uv or incandescent for hackmanite.

 

[pokerface]

If you google hackmanite, you will see dozens of photos that looks basically identical to your stones. Per Wikipedia, hackmanite has been found in Russia. If your stones really were in Russian mines where alex was found, you are right in saying that they were left behind for a reason. You might get more interest/responses on a rock and mineral forum; Pricescope consumers are pretty focused on gem-grade materials.

 

[gt3ale]

Not hackmanite per mineralogist. It doesnt retain colour in daylight. Colour shift only observed under candlelight.

 

[Gloria27]

Not hackmanite per mineralogist. It doesnt retain colour in daylight. Colour shift only observed under candlelight.

Exactly, the effect it is called tenebrescence! Fun!