Color banding in brown diamonds

[Rockdiamond]

Hi PS friends,
Unlike yellow diamonds- where the body color is pervasive, with brown rough the cutter must orient the grain so that the color shows from the face up position. This means that many brown diamonds loose color when viewed through the pavilion.
This photo shows that effect clearly. Sorry for the poor focus.

 

[chrono]

In short, it shows colour zoning, much like blue sapphires, so it has to be oriented so that the colour is played up as much as possible. I saw an interesting blue sapphire very much like the example FCD you showed. The pavilion is almost totally clear except for a very small blue swath, but the lapidary did an excellent job where the crown view shows nothing but an even blue colouration.

 

[Rockdiamond]

"Color zoning" and "Color banding" are interchangeable terms- but yes, many brown diamonds behave like some sapphires in this regard.

 

[lambskin]

How cool! Can you show a face up photo?

 

[Agneau]

I didn't know diamonds had color zoning... that's really cool. I second the request for a face up photo. Thanks for sharing!