what is a window,please?

[pinkjewel]

I'm just learning about colored stones and different cuts and I've been reading a lot here- but would someone mind telling me what a "window" is? I keep seeing the term-but what exactly causes it?

 

[ZestfullyBling]

Hi PinkJewel

I found this definition of "window" on the ACStones website:
"Window: A window is an area under the table of a stone that does not reflect light. It's called a window because light goes through it like window glass. It is almost always undesirable and occurs when pavilion facets are cut below the critical angle for a gem material. To test for a window, hold a gem, face up, with the table parallel to a sheet of newspaper and look through it. If you can read the print, the stone has a window. Most native cut stones have large windows as using low pavilion angles allows a larger stone from a given piece of rough."

http://www.acstones.com/info/Definitions.html

Hope this helps.

 

[pinkjewel]

thank you so much- that does help, although looking at some pictures that people are talking about the stone having a window- I still can't see it

Maybe with time...

 

[FrekeChild]

This should help.

Blue stones- window on right.
Pink stones- window on left.

 

[pinkjewel]

Wow.. that really does show it so well. Thank you!!

 

[LD]

Pink jewel - it's also important to note that a window is only one that you can see when you look at a gemstone head on. It's not when you look at a window and see a similar effect when the gem is viewed from the side - this is called a tilt window. The photos below show a tilt window and this is absolutely nothing to worry about.

 

[pinkjewel]

thank you LovingDiamonds- it is very helpful to see the pictures