Sign in or Register Home
DiamondRing.comYour Online Jewelry Shopping Network
 Ideal Cut Diamond Studs at James Allen 
Buy Sell Education Forum Directory Blog  
View Recent Products View Posts Ask Us Ask our Network Jewelers for a quote on a diamond/gemstone/jewelry




 
Post Reply New Thread
 
Thread Tools Search this Thread
Old pkarhu

    pkarhu's Avatar
 
My Profile
Registered User : offline
Joined: 05-26-04
Posts: 249
Years:
Last seen wearing:
 
My Karma
Power: 68
Points: 352
pkarhu is just really nice pkarhu is just really nice pkarhu is just really nice pkarhu is just really nice


Quote this post and reply to it Post#1 @ 08-30-04 , 05:04 PM


Just a quickie question for the experts...

I've been seeing a lot of gemstones cut in different shapes using the Portuguese faceting technique and they are so vibrant and sparkly. Why haven't diamonds been cut into a Portuguese faceting pattern before? I'd bet they would be beautiful! If this is a stupid question, just tell me so!


pkarhu signature
Diamond Search:

Carat:  to  Color:  to  Clarity:  to  


Old Michael_E

    Michael_E's Avatar
 
My Profile
Network Jeweler : offline
Joined: 01-17-03
Posts: 1,906
Years:
 
My Feedback (23)
Feedback In: 
+14  0
Feedback Out:
+23  0
 
My Store
509-663-6488
Diamonds: 1
Gemstones: 10
 
My Karma
Power: 281
Points: 19475
Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute
Hits: Out=2545, In=1
Referrals: 3


Quote this post and reply to it Post#2 @ 08-30-04 , 06:54 PM


pkarhu,
Portugese cuts are designed to maximize weight retention and depth of color in colored stones. In diamonds that Portugese cut would end up giving you a 1 1/2 to 2 carat stone with the face up area of a 1 carat stone. Since there is usually no advantage to having deeper color, (usually the advantage is in having less color), there is no reason to cut a diamond this way. Actually, if the rough is deep enough, it can be cut in two, which will produce one large and one small diamond in a standard round brilliant. This gives a much greater financial return than in cutting one deep Portugese cut.
If you are cutting an Aqua though , the opposite is true, in that color is paramount and this cut maximizes that.
BTW I thought that was a very good question !


Michael_E signature
Old ArchFool

    ArchFool's Avatar
 
My Profile
Registered User : offline
Joined: 03-13-04
Posts: 96
Years:
 
My Karma
Power: 64
Points: 10
ArchFool is on a distinguished road
Hits: Out=429, In=0


Quote this post and reply to it Post#3 @ 08-30-04 , 10:59 PM


Quote:
Originally posted by Michael_E
pkarhu,
Portugese cuts are designed to maximize weight retention and depth of color in colored stones. In diamonds that Portugese cut would end up giving you a 1 1/2 to 2 carat stone with the face up area of a 1 carat stone. Since there is usually no advantage to having deeper color, (usually the advantage is in having less color), there is no reason to cut a diamond this way. Actually, if the rough is deep enough, it can be cut in two, which will produce one large and one small diamond in a standard round brilliant. This gives a much greater financial return than in cutting one deep Portugese cut.
If you are cutting an Aqua though , the opposite is true, in that color is paramount and this cut maximizes that.
BTW I thought that was a very good question !



Ahhh.. but what about coloured diamonds?

Old Michael_E

    Michael_E's Avatar
 
My Profile
Network Jeweler : offline
Joined: 01-17-03
Posts: 1,906
Years:
 
My Feedback (23)
Feedback In: 
+14  0
Feedback Out:
+23  0
 
My Store
509-663-6488
Diamonds: 1
Gemstones: 10
 
My Karma
Power: 281
Points: 19475
Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute
Hits: Out=2545, In=1
Referrals: 3


Quote this post and reply to it Post#4 @ 08-30-04 , 11:49 PM


ArchFool,
I believe that artificially colored diamonds are treated after they are cut and only colored if they will bring a greater return by being color treated.
If the diamond were naturally colored and of a financially desirable size, then that stone would be given special attention in order to the derive the greatest financial gain from the way that it was cut. If a portugese cut was possible AND would be the most financially advantageous, then that's how it would be cut.
After all what's it all about $$$


Michael_E signature
Old pkarhu

    pkarhu's Avatar
 
My Profile
Registered User : offline
Joined: 05-26-04
Posts: 249
Years:
Last seen wearing:
 
My Karma
Power: 68
Points: 352
pkarhu is just really nice pkarhu is just really nice pkarhu is just really nice pkarhu is just really nice


Quote this post and reply to it Post#5 @ 08-31-04 , 09:37 AM


It's too bad that it's all about $$$...
So, let me ask this...is this why the modern round brilliant came about? Because the OEC cut was too deep and the stone faced up smaller? To me, I think that the OEC cut had much more fire and flash than the modern RB...


pkarhu signature
Old Michael_E

    Michael_E's Avatar
 
My Profile
Network Jeweler : offline
Joined: 01-17-03
Posts: 1,906
Years:
 
My Feedback (23)
Feedback In: 
+14  0
Feedback Out:
+23  0
 
My Store
509-663-6488
Diamonds: 1
Gemstones: 10
 
My Karma
Power: 281
Points: 19475
Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute
Hits: Out=2545, In=1
Referrals: 3


Quote this post and reply to it Post#6 @ 08-31-04 , 12:34 PM


pkarhu,
The modern idea of "light performance" in diamonds is very interesting and has more to do with marketing than it does with reality. If you look at how any diamond behaves optically, almost all of the light entering the crown of the stone will leave via the crown. A stone has to be cut exceptionally badly cut to exhibit "leakage".
The whole idea of modern diamond design is to get a large percentage of the light that enters, to exit the stone perpendicular to the table when you are looking straight at the table, (and to get a pretty, symmetrical, pattern, e.g. H&A). This is fine and makes for a very bright stone when viewed straight on, in many light conditions.
An OEC on the other hand tends to have a tall crown and a small table. This means that most of the light leaving the stone will be leaving at angles other than straight through the table so the stone doesn't look quite as bright. The other effects of this design are that it will sparkle at a wider range of angles as you tilt the stone and the larger angles on the crown will cause the light to spread into a "rainbow" of color with a wider angle than seen on a modern round brilliant. You see this as more multiple colors as you move the stone.
This is one thing that seems to be missing in our modern scheme of things in that everyone is striving to acquire "the best" cut in diamonds, (or anything else for that matter), when in fact the "best" depends on YOUR viewpoint and not on what everyone gets together and agrees is the "best". In my view a high quality OEC is superior to a modern round brilliant in that it shows off the most attractive traits that a diamond has to offer. If a person wants maximum brightness, clarity and symmetry they could just wear a mirror.
Why did diamond design change ? Two reasons.
1. The new round brilliant was new, and brighter.
2. They could get a larger second stone from the other half of the diamond crystal which meant greater financial returns.


Michael_E signature
Old pkarhu

    pkarhu's Avatar
 
My Profile
Registered User : offline
Joined: 05-26-04
Posts: 249
Years:
Last seen wearing:
 
My Karma
Power: 68
Points: 352
pkarhu is just really nice pkarhu is just really nice pkarhu is just really nice pkarhu is just really nice


Thank You!!!
Quote this post and reply to it Post#7 @ 08-31-04 , 01:42 PM


Thanks, Michael_E for answering my questions. You are a wealth of knowledge!!!


pkarhu signature
Old tonysgeko

    tonysgeko's Avatar
 
My Profile
Registered User : offline
Joined: 05-11-01
Posts: 472
Years:
 
My Karma
Power: 91
Points: 1247
tonysgeko has much to be proud of tonysgeko has much to be proud of tonysgeko has much to be proud of tonysgeko has much to be proud of tonysgeko has much to be proud of tonysgeko has much to be proud of tonysgeko has much to be proud of tonysgeko has much to be proud of tonysgeko has much to be proud of


Quote this post and reply to it Post#8 @ 09-23-04 , 09:53 PM


Quote:
Originally posted by Michael_E
pkarhu,
to exit the stone perpendicular to the table when you are looking straight at the table, (and to get a pretty, symmetrical, pattern, e.g. H&A).

Michael I wanted to ask you about the H&A pattern. How would a diamond optically behave if you could facet it so that it shows 16 spokes instead of the usual 8 spokes?

Old Michael_E

    Michael_E's Avatar
 
My Profile
Network Jeweler : offline
Joined: 01-17-03
Posts: 1,906
Years:
 
My Feedback (23)
Feedback In: 
+14  0
Feedback Out:
+23  0
 
My Store
509-663-6488
Diamonds: 1
Gemstones: 10
 
My Karma
Power: 281
Points: 19475
Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute Michael_E has a reputation beyond repute
Hits: Out=2545, In=1
Referrals: 3


Quote this post and reply to it Post#9 @ 09-24-04 , 12:50 AM


tonysgeko,
I think that it would all depend on the size of the diamond, as I don't think that it would look very good on stones under about 5 carats or so. In the cuts that I've done on CZ and colored stones there seems to be a limit to the ratio between the average facet width and the stone size, such that when the average width of the facets gets narrow beyond a certain point, (which happens when you add more and more facets), the stone starts to lose it's sparkle or scintillation. The reason for this is that the angle between any two adjacent facets gets smaller and there is a less distinct change in the level of light reaching your eye as the stone is moved. Basically the stone just plain gets, "fuzzy" looking. On a really large stone it would probably look good, since the average facet width would still be big enough to show independent flashes of light.
If you look at any faceted gem as a cone shaped set of mirrors, (the pavilion), with a set of prisms on top of them, (the crown), it becomes easier to visualize what's happening.
Did that help or just confuse ?


Michael_E signature
Read Messages in: Lapidary All forums
Newer:
Up a Topic asscher or cushion cut sapphire by sassy_1967
Up a Topic which to sacrifice color vs clarity posted in DIAMONDS by doc305
Older:
Down a Topic Looking for a cutter by sassy_1967
Down a Topic which one would u get posted in DIAMONDS by groove
Thread Tools Search this Thread
Search this Thread:
 
Advanced Search

Contact Us - Guidelines - Privacy Policy - Refer a Friend - Top^


Google Custom Search

XHTML | CSS
Logged in as Unregistered
Powered by: vBulletin®
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Copyright © 1998 - Present, DiamondRing.com. oHraDaco.
All times are GMT -4. The current time is 08:07 AM.
Validation #22ccad2d.