White sapphire question (title edited for clarity)

[Owies Nana]

How does a jeweler tell which is which?

 

[FrekeChild]

Re: White sapphire vs. cubic zirconium

There are very distinct visual differences. However, we are not allowed to discuss man made gems here.

 

[Pandora II]

Re: White sapphire vs. cubic zirconium

If they have any gemmological training then very, very easily. One is singly refractive and the other is doubly refractive.

 

[Owies Nana]

Re: White sapphire vs. cubic zirconium

I was just wondering because I have a three stone ring (3ct radiant, 2ctw trilliants) that was sold to me as white sapphire in a 14k white gold setting. When it was sized, the jeweler tried to simply stretch the setting, and as a result, one of the trilliants fell out and was lost.

The jeweler told me that it was extremely difficult to match white sapphires because they range in color from clear to silvery gray (with many shades between), and that mine were obviously all cut from the same stone because they had the same "silver" inclusions. I then had to wait six weeks for the repair due because he said he had to order multiple stones to find one that would match my other stones for color. The one he provided as a replacement is perfectly clear, and in his words "better quality" than the one he replaced. It looks very different from the other stones in the ring.

I am wondering what I would need to do to confirm that the replacement is indeed a white sapphire, and to what lengths I will need to go to get another matching trilliant so that the ring looks more balanced.

Is what he told me true about the color of white sapphires?

And how do I know that a jeweler is skilled at discerning colored gemstones? What qualifications do I need to look for?

Thanks.

 

[gongli]

to confirm the sapphire is not synthetic, one not very expensive and authoritative way is to send the ring to agl for the fast track gembrief report

http://www.aglgemlab.com/services/FastTrack.aspx

they do mounted stones for a slightly higher fee.

 

[Owies Nana]

What do you think about his comments about difficulty in matching the stones? Is it common for white sapphires to have silvery thread-like inclusions?

The "replacement" stone is perfectly clear.

 

[Owies Nana]

What do you think about his comments about difficulty in matching the stones? Is it common for white sapphires to have silvery thread-like inclusions?

The "replacement" stone is perfectly clear.

 

[gongli]

i don't know at all about how common they are in the market ... i just look around on internet dealers, but i did find a few untreated white sapphires with lab reports that the seller says are "flawless"

http://www.sapphires.ca/Unheated%20White%20Sapphires%20win.htm

 

[Pandora II]

White sapphires are reasonably available, and not that expensive. One of the issues I have found with them is that often they have a very slight tint - blue, pink, yellow. It's not really noticeable until you put them next to each other and then it is rather obvious. So matching stones isn't always easy especially if it was for a ring - earrings you can get away with a slight colour difference.

Regarding inclusions, the ones I have are completely clean (flawless in coloured stone means that they are eye-clean at a distance of around 10 inches. They are almost invariably heat-treated which will affect any inclusions present.

I'm not sure what they meant about silvery inclusions - it could be microscopic silk or a veil inclusion, difficult to say.

If the stone is new then it may have a higher lustre to it due to being recently polished, or it may have a better cut and thus better light return which can make a stone look more lively.

You'd really need a lab appraisal to separate a synthetic sapphire from a natural sapphire as they are optical, chemically and physically the same material. There are some inclusions that can indicate natural or otherwise but you need an expert to determine this.