Windows

ShoppingTelly

Help Support ShoppingTelly:

Greenie

Addicted to bling
Joined
Aug 2, 2009
Messages
190
Since seeing Meeshoo’s pic of her rose de france amethyst ring with the massive window (see Sparkly New Stuff post), I’ve become kinda interested in windows, so much so that I looked at all my GemsTV purchases to see whether they had any. Out of all the pieces I have, only the green amethyst stones (which are quite pale in colour) possessed any sort of window, some a bit bigger than others.

I looked on the ‘Gemopaedia’ on the website under Lustre, Brilliance & Fire and came across a paragraph and attached diagram about windows. It says:

"Certain cutting angles allow the light to pass straight through the gem (commonly called a “window”) or to be deviated to the side. Accurate cutting to optimum angles will allow light to travel back towards the viewer when looking directly into the table facet."

This suggests to me that they’re saying if a gem stone has a window it has not been cut accurately. My question is if this is the case why are these gems passed by quality control and get set into jewellery? It’s kind of like selling off ‘seconds’. I would have thought Gems have standards to keep up and would reject these badly cut gems? Or have I got it all wrong?
 

Attachments

  • too-shallow.jpg
    too-shallow.jpg
    6.5 KB · Views: 156
Some great research Greenie.

I'm going to link to a thread below that I wrote a while ago that shows examples of windows, extinction and I can't remember what else!!!

You asked why these gems pass QC? It's quite simple. There's actually nothing wrong with the gem itself. These gemstones are just poorly cut. So for example, they're labelled as, say, a Tanzanite and what you get IS a Tanzanite. However, if you buy a high end gemstone at a high end price, you should expect a well cut gemstone BUT the majority of affordable gemstones on the market are poorly cut. You'll see these also termed as "native" cuts. There's nothing wrong with the gemstone per se, it's just been badly finished. A bit like comparing a well cut item of clothing to one that has hems not finished properly! So in some ways, it's like comparing designer, limited in number, clothes to mass produced clothes for the general market.

Windows are caused by the cutter (normally) attempting to maximise gemstone weight. So for example, to cut a well cut stone from a piece of rough, the finished stone might be .80 of a carat. By cutting it so that it's shallow and has a larger face, the lapidarist might be able to get a gemstone of 1ct or higher. Thus, the gemstone weighs more and in theory should cost more BUT it will be at the expense of it's beauty.

You have to understand that most people buy jewellery because they love the colour or the look. I'm afraid it's only when you become an anorak like the rest of us that you then start to see things that could be improved.

Unfortunately, some companies (eg Rocks and Co - that'll earn me another bashing by one of their employees :giggle:) try to sell badly cut gemstones for a high end price tag. That's unacceptable but they get away with it until people become educated and look elsewhere.

However, one rider I need to add here ............ some gemstones are considered so desireable that they are routinely native cut and finding a well cut example is more difficult (not impossible though). Alexandrite and proper Paraiba Tourmaline are two such gemstones.

I personally have a few gemstones that, despite having windows, I've kept because they're unique in other ways.

http://www.shoppingtelly.com/forum/showthread.php?t=8213&highlight=extinction
 
I love everything including the rough stone. It all has its own character. I have a large piece of amethyst in a ring that is a mass of inclusions, but it has its own kind of charm BUT it was accordingly extremely inexpensive.

I get so angry when any of the channels try to pass off everything as perfection, if it weren't for that I think a lot of us would find faults and imperfections acceptable. xxxx
 
I agree Argey. Some inclusions are fascinating and if the gem is priced accordingly, why not! I have an included Alexandrite but the silks emphasize the colour change. In a Ruby I have a tiger stripe inclusion that helps to classify the gemstone as natural etc etc. The most fascinating - and I don't have one of these - is when you see insects trapped in amber. Unfortunately modern technology means this can be done with synthetics but all the same, fascinating!
 
Unfortunately, some companies (eg Rocks and Co - that'll earn me another bashing by one of their employees :giggle:) try to sell badly cut gemstones for a high end price tag. That's unacceptable but they get away with it until people become educated and look elsewhere.

I get so angry when any of the channels try to pass off everything as perfection, if it weren't for that I think a lot of us would find faults and imperfections acceptable. xxxx

1.gif

4 days 22 hours 19 minutes to go until
6.gif


But for now.....................
10.gif
 
C'mon Klos ya know you want to, you know you 'ave to, it'll only make you ill to keep all that in, open - just a little <a href="http://plugin.smileycentral.com/http%253A%252F%252Fwww.smileycentral.com%252F%253Fpartner%253DZSzeb008%255FZNxpt484YYGB%2526i%253D36%252F36%255F20%255F7%2526feat%253Dprof/page.html" target="_blank"><img src="http://smileys.smileycentral.com/cat/36/36_20_7.gif" alt="SmileyCentral.com" border="0"><img border="0" src="http://plugin.smileycentral.com/http%253A%252F%252Fimgfarm%252Ecom%252Fimages%252Fnocache%252Ftr%252Ffw%252Fsmiley%252Fsocial%252Egif%253Fi%253D36%252F36_20_7%2526uiv%253D3.0/image.gif"></a> xx
 
You asked why these gems pass QC? It's quite simple. There's actually nothing wrong with the gem itself. These gemstones are just poorly cut. So for example, they're labelled as, say, a Tanzanite and what you get IS a Tanzanite. However, if you buy a high end gemstone at a high end price, you should expect a well cut gemstone BUT the majority of affordable gemstones on the market are poorly cut. You'll see these also termed as "native" cuts. There's nothing wrong with the gemstone per se, it's just been badly finished. A bit like comparing a well cut item of clothing to one that has hems not finished properly! So in some ways, it's like comparing designer, limited in number, clothes to mass produced clothes for the general market.

Thanks Meeshoo for this great post. It all makes sense now. And also for the link to your other post on Problems with Gemstone Cuts which was SO informative. Do we have 'sticky's' on here? I was wondering if it could be made into a sticky as it's really excellent information for newbie collectors like myself?
 
Last edited:
Go Klos, you're doing extremely well. I've even copied you on another thread (but couldn't find the smilie with a cross throught the mouth!) and you know that imitation is the sincerest form of flattery.
Don't listen to Argey, she's using all her wiles and deviousness to win the bet, you can do it! :clapping:
 
Thank you to Greenie & Meeshoo (for the additional thread link) for posting about this - not something I really know anything about at all, always interesting & useful to learn something new! :up2:
 

Latest posts

Back
Top