Purple spinel

[T L]

I freely admit that I''m really stupid when it comes to spinel (I''m sure everyone else noticed as well - LOL). Therefore, how does purple spinel differ from a stone like amethyst - in color only. I know it''s more dispersive than amethyst, but does purple spinel sometimes come in a very pure grape form of purple?

 

[knitwit]

I''d like to know that too TL as I am really new to buying colored gemstones and my last two purchases were an amethyst and a purple spinel!

 

[FrekeChild]

I''ve seen violet and lavender spinel. Don''t remember purple, but haven''t looked for it either. My spinel turns bright amethyst purple when under fluorescent lights...

 

[MakingTheGrade]

Date: 3/30/2009 6:01:10 PM
Author: FrekeChild
I''ve seen violet and lavender spinel. Don''t remember purple, but haven''t looked for it either. My spinel turns bright amethyst purple when under fluorescent lights...

I''ve actually wondered about that. Most of Dan''s blue spinels seem to color shift to purple in some lighting. Is that the norm for spinels?

 

[T L]

Well the reason I''m asking is that Dan has posted some purple spinels, and typically I see violet in purple spinels. These are more of a straight purple, so I was wondering if that did exist. There was actually a purple spinel I was eyeing, and I wanted to know if there was anything different about the color than an amethyst.

 

[LD]

I find that in general purple spinels have a grey undertone.

 

[T L]

or a brown undertone as well??

 

[LD]

Date: 3/30/2009 6:43:19 PM
Author: tourmaline_lover
or a brown undertone as well??

I haven''t seen brown. Only grey. I think that''s why the purple doesn''t do it for me. It''s a cold purple and I prefer a warmer tone.

 

[knitwit]

Dan described the purple spinel I just purchased as medium purple with pink flashes. I''ve never seen a purple spinel so I''ll be interested to see if it more purple or more violet.

 

[chrono]

I have seen first hand a top purple spinel with no gray, violet or brown. Of couse it wasn''t cheap either. I reviewed it during my search for my elusive blue spinel and thought this might be a very pretty colour changer and it is.
http://www.kingdomofredspinels.com/showdetail_pro.asp?product_id=591

 

[T L]

I like the picture of the lavender flower that they showed as a companion photo to this stone. That gives you an idea of what to look for in optimal purple spinel I would guess.

 

[Barcelona]

Author: LovingDiamonds
I think that''s why the purple doesn''t do it for me. It''s a cold purple and I prefer a warmer tone.

I feel the same way. I''ve come across a few nice looking purple spinels, but I''m just not sold on them.

 

[BWise]

I have not seen enough purple spinels to answer TL''s question, but I would concur with LD that most spinels have grey or pink under tone to it and has a cold feeling. Amethyst has a warmth, reddish undertone to it.

Date: 3/30/2009 6:47:58 PM
Author: LovingDiamonds

Date: 3/30/2009 6:43:19 PM

Author: tourmaline_lover

or a brown undertone as well??

I haven''t seen brown. Only grey. I think that''s why the purple doesn''t do it for me. It''s a cold purple and I prefer a warmer tone.

 

[ma re]

I''ll try to keep this as short as possible, but there are some important differences between the two.

For starters, it''s the shade of color. There are some nice purple spinels but probably 99% of them are either pastel(ish) shades or quite dark ones. Spinels with a color saturation of a fine African amethyst are EXTREMLY rare and equally expensive.

Next in line is refraction of light. I''m surprised that some experienced posters haven''t thought of this, but spinel not only has a MUCH higher R. I., but it''s also singly refractive, which makes it''s brilliance much crispier and sharper, but it also makes the stone more scintillating than an amethyst.

And birefringence of amethyst adds another important difference - pleochroism. Now, TL, of all people for you to forget about this optical property for which tourmalines are famous...?!

It''s the reason why the best of amethysts can show red, blue and purple at the same time, while spinels can not, due to the fact that they form in a cubic crystal system.

Hope this helps

 

[knitwit]

You are such a wealth of information Mr. ma re. I love reading your posts. It''s kinda like being in a gemstone classroom.

I will be sure to take photos of my new purple spinel when it arrives as it appears in photos to be very grape like in color. However I am aware that some of Dan''s photos haven''t always translated IRL but I also read that he changed his lighting set up. I will post pic when it arrives.

Thanks again for the "education" and to TL for posing the question in the first place.

 

[T L]

Date: 3/31/2009 3:59:47 AM
Author: ma re
I''ll try to keep this as short as possible, but there are some important differences between the two.

For starters, it''s the shade of color. There are some nice purple spinels but probably 99% of them are either pastel(ish) shades or quite dark ones. Spinels with a color saturation of a fine African amethyst are EXTREMLY rare and equally expensive.

Next in line is refraction of light. I''m surprised that some experienced posters haven''t thought of this, but spinel not only has a MUCH higher R. I., but it''s also singly refractive, which makes it''s brilliance much crispier and sharper, but it also makes the stone more scintillating than an amethyst.

And birefringence of amethyst adds another important difference - pleochroism. Now, TL, of all people for you to forget about this optical property for which tourmalines are famous...?!

It''s the reason why the best of amethysts can show red, blue and purple at the same time, while spinels can not, due to the fact that they form in a cubic crystal system.

Hope this helps

I have a pink spinel that shows pink and purple at the same time - making it kind of look like an orchid. Does that count, or do you think it''s more of a color shifter? In incandescents, it goes more pink, but in fluorescent or natural light, it shows a violet to the pink.

 

[ma re]

Knitwit, thank you for your compliments, I''m just a hobbyist like most folks here. I also don''t mind sharing knowledge whenever I can be of help - nice to know someone appreciates it.

TL, I''d say that your spinel is some sort of a color shifter (although I''m not that much of a scientist to explain everything), and if it''s a precision cut stone that might also play a role, cause good cutters can make the colors mix within a material, by using proper facet arrangements and angles.