Fluorescence - lots of colours!

[OoohShiny]

I just stumbled upon this on youtube - terrible quality but pretty awesome!

 

[Lachinoiserie]

Impressive! Nice little collection.

Source: http://blogs.nature.com/london/2007/11/28/minerals-bring-new-sparkle-to-museum

 

[redwood66]

That's cool! Colorful Christmas tree!

 

[Texas Leaguer]

Very cool!

 

[Karl_K]

kicken!!!
Thanks for posting!!!

 

[marcy]

Awesome

 

[elle_71125]

Wow. That was awesome.
I actually really love fluorescence in diamonds because you can play with them more. It's really cool to see so many different colors in one place.

 

[RetroTreeGal]

I want my bedroom ceiling to look like that now.

 

[tyty333]

That is very cool!

 

[OoohShiny]

I just found this GIA article on Flourescence after @cflutist posted a link to a similar article on Pear-shaped diamonds:
http://4cs.gia.edu/en-us/blog/fact-checking-diamond-fluorescence-myths-dispelled/


I thought it was really good, and it has a cool photo of various coloured fluor!
http://4cs.gia.edu/wp-content/uploads/2018/03/2931-690x460-diamond-fluorescence.jpg

It looks like Harry Winston might actually be using fluor as part of its design choices - check out the photos of this 132ctw necklace!
http://4cs.gia.edu/wp-content/uploads/2018/03/20652-690x460-bejeweled-fireworks.jpg

 

[PrismBaby]

This is so neat!

 

[Lorelei]

Very cool and I can imagine a cobweb necklace with those pretties, a true Necklace of Raindrops.

 

[Lorelei]

I just found this GIA article on Flourescence after @cflutist posted a link to a similar article on Pear-shaped diamonds:
http://4cs.gia.edu/en-us/blog/fact-checking-diamond-fluorescence-myths-dispelled/


I thought it was really good, and it has a cool photo of various coloured fluor!
http://4cs.gia.edu/wp-content/uploads/2018/03/2931-690x460-diamond-fluorescence.jpg

It looks like Harry Winston might actually be using fluor as part of its design choices - check out the photos of this 132ctw necklace!
http://4cs.gia.edu/wp-content/uploads/2018/03/20652-690x460-bejeweled-fireworks.jpg

I'll be sending Dancing Fire a link to that HW necklace, I believe he should buy it for me.

 

[Dancing Fire]

I'll be sending Dancing Fire a link to that HW necklace, I believe he should buy it for me.

I can afford the necklace in USD but not in British Pound...

 

[Lorelei]

I don't care DF, USD is fine with little old me, just buy it.

You know you want to.

 

[OoohShiny]

Just stumbled on the page on the Natural History Museum website that gives more info on these

http://www.nhm.ac.uk/discover/how-do-coloured-diamonds-form.html

Copy of text below, in case it disappears!

http://www.nhm.ac.uk/content/dam/nhmwww/discover/coloured-diamonds/pyramid-hope-2-full-wdith.jpg
PIC: The Aurora Pyramid of Hope on display

COLLECTIONS
How do coloured diamonds form?
By Katie Pavid
First published 28 April 2017

Mike Rumsey, Senior Curator of the Mineral collection at the Museum, explains how the stones naturally developed such bold shades:

'Perfectly formed diamonds composed only of the element carbon, with no chemical impurities, no internal defects and no extra particles would be completely colourless.

'But nature rarely produces perfect objects. In the case of diamonds, it is these imperfections that cause colour.'

How are diamonds formed?
These precious gems are formed deep in the Earth's mantle - the layer between the crust and the planet's core.

The mantle experiences extremely high temperatures and pressures, up to 160 kilometres below our feet.

No scientist can travel that far underground, so we don't know exactly how diamonds are created. But we know they are formed of carbon atoms coming together under intense pressure and heat to form crystals.

The stones that we mine today are not this deep. They were brought up from inside the planet by huge and ancient volcanic eruptions.


PIC: Robin Hansen, a mineral curator, admires the collection



Mike says, 'The different geological environments and formation processes are what causes imperfections in the stone - and these are what give diamonds their colour.'

Many diamonds actually show very pale colours, most often in shades of yellow, brown and grey. They are rejected as gemstones and used in industry instead, often as abrasives.

However, on the rare occasions when the colour is more intense, they become extremely desirable.

Yellow and brown diamonds
The majority of natural diamonds contain nitrogen atoms as impurities in their internal structure. These impurities produce a yellow or brown colour.

Mike says, 'Because nitrogen is so widespread, it is no surprise that pale tints of yellow and brown are the most common coloured diamond.'

The colour is affected by how the nitrogen is scattered through the stone.

If single nitrogen atoms replace carbon, the diamond can be bright canary yellow. If the nitrogen atoms are clustered around missing parts of the internal structure (tiny holes that mineralogists call defects) a paler yellow called cape is produced.


http://www.nhm.ac.uk/content/dam/nh...-diamonds/pyramid-hope-glowing-two-column.jpg
PIC: Some diamonds glow under UV light



These diamonds also glow fluorescent blue under ultraviolent (UV) light. The Aurora Pyramid of Hope collection contains several diamonds that do this.

Brown diamonds are caused by the crystal becoming deformed. Their internal structure is warped, creating tiny holes which cluster and affect the way light passes through the stone.

Deep blue and green diamonds
The chemical element boron makes diamonds go blue when it finds its way inside them.

Blue diamonds only need a tiny amount of boron to produce colour, but they are much rarer than yellow ones.

A green diamond means it has been near radioactive mineral at some point in its history.

Mike says, 'Depending on the type of radiation that the diamond was exposed to, the green colour may just be on the surface, or evenly spread throughout the entire crystal.

'It is easy to irradiate objects, so green diamonds are produced synthetically too. Sorting a natural example from one produced in a lab is not always possible.'

The rarest hues
Naturally coloured red diamonds are extraordinarily rare, and scientists are still not completely sure what causes their rich colour.

It is thought that the colour in red and pink diamonds is caused by a change in the structure of the crystal called plastic deformation, possibly in combination with another internal defect.

This distortion changes the way light interacts with the atomic structure of the diamond as it passes through the stone, causing it to look red or, more often, pink.

Purple diamonds exist but are almost never found because one stone must be exposed to both the red and blue causes of colour change to create the blend.

Mike says, 'Perhaps the most intriguing of all the coloured diamonds is the chameleon. At the apex of the Pyramid of Hope is a six-carat diamond that can change colour. It will go from olive green to yellow when it is exposed to light after a period of time in the dark, or when it is gently heated.'

The internal mechanisms, impurities or imperfections responsible for the diamond's change in colour are still being researched.

Mike says, 'It is probably due to a combination of factors and includes a significant presence of both hydrogen and nickel atoms.'

See the display
The Aurora Pyramid of Hope is on permanent display in the Vault.

 

[OoohShiny]

Stumbled upon quite a cool picture of different flour colours and how they vary with different wavelenths of light within a YouTube video on man-made / laboratory grown diamonds, from what I can tell - check out 3:03!

I think that sort of thing might be what Garry and Todd(?) have been going back and forth on in the 'Overgrading of diamonds' thread! (or whatever it's titled lol)


(Oh, and I smiled at the 'Real is Rare' slogan in the video that was followed a short while after by 'global mined production is c.125m ct/year... )

 

[Demon]

I love fluorescence so much. That 1st video is great!

 

[bmfang]

(Oh, and I smiled at the 'Real is Rare' slogan in the video that was followed a short while after by 'global mined production is c.125m ct/year... )

I always find it hilarious whenever I hear B&M jeweller sales associates tell me that diamonds are very rare.

I usually end up correcting them by saying that “Diamonds that meet my exceedingly anally retentive specifications are very rare.”

Which has put me in some uncomfortable situations when they ask me whether any of the stones they have on offer in store meet my specs. I have to be ... erm... very diplomatic, most of the time.

 

[OoohShiny]

I always find it hilarious whenever I hear B&M jeweller sales associates tell me that diamonds are very rare.

I usually end up correcting them by saying that “Diamonds that meet my exceedingly anally retentive specifications are very rare.”

Which has put me in some uncomfortable situations when they ask me whether any of the stones they have on offer in store meet my specs. I have to be ... erm... very diplomatic, most of the time.

haha!

I was looking in some shop windows earlier today - some classic 'frozen spit' stones for something like £5k for 1ct... No thank you!! lol