What light does diamond give off under direct sunlight?

[Ashleigh]

I'm sure your diamonds must have throw out light under direct sunlight. What light is that? Is it light or Fire? Cos I realized that my diamonds behave differently under direct sunlight and I wish to pinpoint which angles are responsible so that I know what to look for in my next diamond.

Diamond 1: throw out blue and red mostly and I need to squint at times

Diamond 2: just white and can look at it directly

Diamond 3: colorful and can look at it directly

Weird huh? All behave differently and are all h&a and score under 2 on hca.
Pls advise. Thank you.

 

[Rhino]

HI Ashleigh,

Good question. The answer can vary based on a few factors. I'll expound.

Direct sunlight is one of the strongest forms of spot lighting there is and you are generally going to always see what the labs define as "fire"/"dispersion" and the type of scintillation commonly referred to as "sparkle scintillation" (as opposed to patterned scintillation).

In the direct/spot lighting environment ideal cut diamonds of virtually all varieties (not just 57 faceted rounds but also princess cuts, cushion cuts, other modified rounds with more than 57 facets, etc.) will experience a phenomena where the body of the diamond itself can generally go dark, however the flashes of fire and sparkle more intense than non ideal cuts. There are many threads on the forums over the years asking "Why does my diamond go dark when I bring it in sunlight?" or questions to that effect. I have these views included in a video I shot on "What Diamond Color Isn't" for further reference if you care to see what I'm talking about.

At the same time however not always will the body go dark. When it doesn't it is generally because there are enough other elements in the environment that the diamond is reflecting back to the viewer. For example if you are outside in direct sunlight, with the sun hitting the diamond directly and there also happens to be a wall in the environment upon which the crown facets are also drawing in reflections from, then you will see fire/sparkle combined with the reflections of the wall reflecting in the crown and the body can go light instead dark. Another example and one which I love is observing (and filming) diamonds in direct sunlight yet under a somewhat shady tree. The diamond with ideal optics will reflect back the fire/sparkle from the sun yet at the same time reflect back various shades of green and/or even a combination of pastels back to the eye of the viewer. It is a beautiful site to behold. I've captured this on film too ... so pretty.

Hope that helps.

Kind regards,
Rhino

 

[Ashleigh]

Jon, thanks for the reply. Now I know the words I'm looking for are fire and sparkle. I've seen only Diamond 1 go dark under direct sunlight, Diamond 2 didn't, must check on Diamond 3 tmr. All turned pastel under trees. I suppose the only way to get the fire and sparkle I like is just to ask the vendor to take it out into direct sunlight with no trees and check for the color of the fire and sparkle. I like pastel. Don't like the blue, red, green combo.

 

[Rhino]

Jon, thanks for the reply. Now I know the words I'm looking for are fire and sparkle. I've seen only Diamond 1 go dark under direct sunlight, Diamond 2 didn't, must check on Diamond 3 tmr. All turned pastel under trees. I suppose the only way to get the fire and sparkle I like is just to ask the vendor to take it out into direct sunlight with no trees and check for the color of the fire and sparkle. I like pastel. Don't like the blue, red, green combo.

Hi Ashleigh,

Just some comments based on your answer ...

While pastels can be observed in diamonds with thin, splintery faceting like modern/modified rounds, modern faceted cushions, princess cuts, etc. they are more pronounced and prominent in vintage cuts with wider, broader faceting that have ideal optics or optics approaching ideal. One reason why the issue of light performance is so important when it comes to cut quality in any shape. In ideal vintage cuts you'll see pastels even when you aren't necessarily under a tree either.

With regards to the colors you are looking for, be it in fire or pastels ... if you are looking for particular colors regarding fire and/or pastels you may be searching in vain because when it comes to fire and dispersion there are always 2 colors that are most prominent in diamond. Those 2 colors being blue & yellow. Sure you will catch some red, green, violet and other colors within the ROY.G.BIV spectrum but these other colors are only seen more rarely and will exist in any diamond exhibiting superior fire.

In brief, pastels will be more dependent upon the surrounding environment, the lighting and the diamonds optical properties and not necessarily in direct light. The colors you will see in direct light of fire will mostly be blue & yellow with hints of the other colors of the spectrum less prominent.

Sounds like a fun shoot! Keep us posted.

Kind regards,
Rhino