Antique Diamond Guide

[madelise]

I think there needs to be a collection of info all "stickied" to one thread that everyone interested can go refer to for an education. Can you please post threads that all the old cut gurus gave wonderful advice for "what is" and "how to choose" at? Or post questions that are commonly asked, or that you may possibly want to ask now?

Here's a few that I wanted to ask or feel are good to include:
- Can someone label/diagram the terms commonly used in old cuts? Ie. Culet, kozibe effect, fish eye effect, nail head effect, higher crowns, check board patterning, snowflake/flower, etc.
- Why there's a culet and the history of the then perceived "safety" of cutting off the lower point.
- What's the difference? between an OEC, OMB, and transitional? Descriptive differences as well as time period differences, play-on-light differences? Why do some OECs have certificates calling them Round Brilliants, yet that same company will issue a certificate for another stone as a European Brilliant? A list of % qualifications for it to be a European vs. a transitional?
- What tools are needed? to make an educated purchase?
- A list of vendors to contact that specialize in old cut diamonds, simplified with no glorifications so that each buyer can choose their own preferred paths to purchase.
- An explanation on the play of color in old cuts, and why they face up whiter when compared to modern rounds or cushions.
- An explanation on depth and why old cuts are deeper and face up smaller than moderns because of the higher crowns, etc. I think some consumers may get shocked at the depth of OECs, and want to run away since their education might be from modern cuts.

 

[madelise]

oh, and I wanted to add a thought that we probably shouldn't link to any thread saying so-and-so-vendor's this stone is poor compared to so-and-so-another-vendor's that stone that is better.. since it might confuse seekers to thinking its the vendor not the particular stone? Does that make sense, or is that much I don't want a dueled out debate, lol! Just information all gathered nicely for future oldies lovers.

 

[GemFever]

This sounds like an excellent idea, and I'll be following this thread closely! If I can remember where I found useful explanations in previous threads, I'll try to come back with quotes from our experts.

 

[madelise]

This sounds like an excellent idea, and I'll be following this thread closely! If I can remember where I found useful explanations in previous threads, I'll try to come back with quotes from our experts.

Yes, this is what I really *needed* a few weeks ago! And still do need! Quotes would be great and maybe images? I just think it gets too overwhelming for searchers to get information because they end up on a thread (like mine) which includes about 20% actual information, and the rest is just me whining or crying about my stress, and then fluffed out with a lot of "ooh that's pretty" comments. The actual tidbits of info gets lost amongst the rest of everything else.

What were some Q's you had, GemFever, when you were seeking?

Heh, I *barely* realized what kozibe effect was just recently. I googled it and searched PS for a good explanation since FOREVER ago when I first saw the comment on one of JbEG's items. Everything I found wasn't telling me or showing me what it was, only explaining it. I finally realized it when looking at someone's SMTB thread a few months ago, and wondering "Why are there so many HOLES in that diamond?! Why does it have more than one culet?!" and it clicked.

 

[Sky56]

Great idea. Maybe, if a compilation of threads isn't done, it could be a stickied guide that those people could put together, kind of like that colored diamond guide put together last year or so by our diamond pals.

 

[fridays_child]

I am certainly not the person to answer any of the questions you posted (all great Qs), but I can answer your call for a helpful thread.

Yssie's OEC earring thread was EXTREMELY helpful to me as I was looking at old stones. This link is to page two, where Yssie posts several links to threads/articles and talks about "mushiness" in OECs. But read through the whole thread, it's very interesting, and Yssie is one very smart gal!

[URL='https://www.pricescope.com/forum/show-me-the-ring/my-studs-are-growing-up-t165839-30.html']https://www.pricescope.com/forum/show-me-the-ring/my-studs-are-growing-up-t165839-30.html[/URL]

My own random thoughts on buying old stones from my limited experience -

Prepare for the stone to look much smaller in real life if you've been viewing macro video/photo. Do study lots of pictures so you can see what you like and don't like. Tastes vary greatly, and it's best to come up with *your own* picture of what you like in an old stone. Also prepare the possibility that the stone will appear somewhat different in real life than in video/photog. If you're looking at a video/pic of a stone in fiery evening sun, well of course that stone (and any other stone) will look amazing. Everything has an amazing cast in early am/late pm sunlight. But if the stone looks great in more pedestrian lighting situations, it has a much better chance of looking great all the time, in my opinion.

Look for very clean crisp facets (what I learned fom reading Yssie's posts). Look for a lively stone. When I opened the package that had my own stone in it, it had a glow to it that I have not seen in some of the other stones I looked at. I I were buying another stone, I would definitely want this "glow".

Don't get hung up on a certain vendor. (This happened to me at first, because there are certain vendors that have a very vocal PS following). Shop around and ask (nicely) for the best price. A vendor with good return policy is a MUST.

Hope that helps.

 

[fridays_child]

Found a helpful post on a characteristic that old cut stones can often have - chips/nicks in the girdle or a bruted girdle:

[URL='https://www.pricescope.com/community/threads/calling-dave-atlas-and-other-old-cut-specialists.72882/']https://www.pricescope.com/community/threads/calling-dave-atlas-and-other-old-cut-specialists.72882/[/URL]

 

[fridays_child]

Another thread, this one on white vs colored light and a touches a bit on head obstruction in old stones:

[URL='https://www.pricescope.com/community/threads/yssie-can-i-get-your-advice-on-these-numbers.168956/']https://www.pricescope.com/community/threads/yssie-can-i-get-your-advice-on-these-numbers.168956/[/URL]

 

[fridays_child]

This goes along with Yssie's undesirable "mushiness" factor to avoid when looking at OECs and also talks about the large flashes of light in an OEC vs the splintery ones of an MRB:

[URL='https://www.pricescope.com/community/threads/strmrdr-virtual-facets-on-oec.91696/']https://www.pricescope.com/community/threads/strmrdr-virtual-facets-on-oec.91696/[/URL]

And even though this article is specifically about step cuts, this is a good explanation of virtual facets:

https://www.pricescope.com/journal/virtual-facets-and-patterns-discussion-about-step-cuts

I personally find all these articles/posts by the pros incredibly interesting, but stop me if this is not what you are looking for

EDIT - I really need to add the original thread that prompted glitterata to ask about OECs and their virtual facets. Read the content in all three links, it's great reading for anyone interested in any old cuts, light performance and virtual facets. Even though at the end of the day, there's just something irresistable about old stones - without even thinking about all this science-y stuff.
[URL='https://www.pricescope.com/community/threads/my-asscher-looks-so-cool-in-low-light-anyone-else.83928/']https://www.pricescope.com/community/threads/my-asscher-looks-so-cool-in-low-light-anyone-else.83928/[/URL]

 

[ericad]

Wow, I'd love to take a crack at this! But being a trade member, not sure if you guys prefer that type of input, or if you're leaning more towards input from other consumers (best practices, etc.)

I'm traveling this weekend, but perhaps this is something I'll want to work on in the coming weeks anyway, and y'all can just let me know what you think (with mod's approval, of course!)

Maybe this can be posted as a trade member article, or something along those lines...

 

[fridays_child]

Wow, I'd love to take a crack at this! But being a trade member, not sure if you guys prefer that type of input, or if you're leaning more towards input from other consumers (best practices, etc.)

I'm traveling this weekend, but perhaps this is something I'll want to work on in the coming weeks anyway, and y'all can just let me know what you think (with mod's approval, of course!)

Maybe this can be posted as a trade member article, or something along those lines...

I made a suggestion in the suggestion box forum that a professional write up an article on antique stones, it seems like many would find it very useful!

 

[madelise]

I was hoping to comb through my thread as well as a few others that were helpful to me in the next few weeks when I have more time, and post key excerpts. I thought I'd have it this week, but I'm thinking I posted too early I haven't had any time!

Trade help would be great, Erica! Ever since I "joined the other side", I've been more and more intrigued by the different eras and the different patterning and development as time passed. Just in the last 2 years of being on PS, I've already seen a huge increase of people being interested in the old chunky flashes. I think many people will find any educational behind old cuts and new old-style cuts very useful.

Even jewelry related information might be good. I'm thinking of, say, showing what the "key" signature looks for each time period/era. Like, what's the difference between the styles during the Georgian, Victorian, Edwardian and Art Deco eras? There's also very little educational information about rose cut diamonds too! Can't leave those babies out of the educational

 

[yennyfire]

What a fanastic idea madelise!!

Erica, I think your input would be fantastic!

 

[bright ice]

What a fanastic idea madelise!!

Erica, I think your input would be fantastic!

1+

 

[GemFever]

What a fanastic idea madelise!!

Erica, I think your input would be fantastic!

1+

and + another 1!

 

[GemFever]

I really hope this thread keeps going. Here are some of the questions I had before purchasing my first antique stones:

- The basics: what’s the difference between an OEC [Old European Cut] and an OMC [Old Mine Cut]. In my understanding, OMC is technically an older style, and mainly defined by a cushiony shape. I also have some ideas about OEC/OMC faceting differences, but I’m not sure how well I understand this. Would love to learn more about it.

- As a non diamond expert, how can I tell if a stone I’m buying is a good one? How to judge its performance, in the absence of strict RB-like guidelines? Here is a quote of some advice I found useful in your thread, Madelise.

Circe asked “Re: the question of stones going dark ... this is something that I was just trying to puzzle out with Dreamer's advice in my SMTB thread, and that was sort of addressed in Mara's RT thread from earlier in the week. If it goes dark to the point of being a nailhead, boo! But if it's what I think it is - where the center facets go on-off, on-off in the light? I actually sort of like it in an old cut. See how it performs in person and whether it pleases your eye ....”

To which Dreamer responded: “On-off-on-off is good What you don't want is the off to be more common than on, and for like one small facet to be on and the other 10 off in one region! Ideally, all the facets go on-off-on-off as you move independently! If soo many are all synced up, you get an "over dark" appearance as a vast swath of the stone darkens, or you get an area that is almost always dark except when you hold your hand juuust right.”

I will add that after countless hours of examining my OMCs under various light conditions, I definitely observe the on-off effect. When I’m looking really close into the stone, I sometimes have to put effort into catching a reflection off one of the main facets under the table. However, the middle of the stone never looks dead when I look at it from a distance. Maybe it’s my head getting in the way of the light when I examine it too closely? Also, my stones are set in a kind of faux-bezel. I wonder if the pavilion were free to receive light, how that would affect performance.

- I didn’t have much experience with modern RBs, so I was very curious how antique stones (and my AVC, for that matter) compare to these modern powerhorses. Somewhere I read a great description of the “speed” of the diamond’s scintillation. The bigger facets of OEC/OMCs produce slower scintillation, whereas RBs are faster. Then there is also the size of the flashes, with RB producing more needlelike flashes, and the antique cuts producing fatter flashes, but less often than the RB’s splinters.

There are plenty more topics to cover, but those were my two main questions before buying: how do I know than this antique stone is a good one, and how will it compare in performance to the more common types of diamond cuts available today?

Then, after buying the diamond and examining it for countless hours, I ended up with a new question:

- When is an antique diamond a good candidate for a repolish? The reason I want to know about this is because I noticed that the edges of the facets on my stones are not crisp and invisible (this is apparently only in certain kinds of light conditions, but especially in jewelry-store lighting). Instead, they look kind of dusty… Which on the one hand makes the facets more distinctive, but on the other makes the stones look… well, not well polished. So the question is – is this just a part of certain antique stones that should be preserved, or is it worth repolishing? What would a repolish entail? How much does it cost? Where does one find a cutter/polisher who specializes in antique stones? This is something I’m still actively pondering.

I think I’ll end here for now, though I have more questions still (primarily related to getting lab reports for antique stones – which one, how, etc).

Thanks for those great links fridays_child! They are great!

 

[Dreamer_D]

I am too lazy to dig up everything I have said on these topics at the moment but I'll take a stab at a couple here while I procrastinate making some dinner for me and hubs.

- What tools are needed? to make an educated purchase?

If you are talking about the primary market and you are buying with the help of a trusted vendor, then all you really need are your eyes And, if it is a substantial purchase of a stone with no lab report or an EGL report (most likely) then the help of an appraiser is also warranted in my opinion, to help you determine fair market value. Appraisers are not all created equal in this area, though. I know of a few people who have been very disappointed with some appraisers with good reps on PS, when assessing old stones. My anecdotal impression is that cut quality and rarity of a certain type of cut is not always taken into account when the appraiser sets the stone's value, but it does get taken into account with askig price. Food for thought.

If you are buying on the secondary market and looking for steals, like ebay or a local estate shop... well I don't really recommend it if you are new to old cuts or new to diamonds! But if you wanted to take a stab at it, these are the tools I use:
- a 10x loupe
- digital calipers
- some diamonds of your own that are graded by a lab like GIA (preferrably something in the G-H range and something in the J-K range)
- well trained eyes for what constitutes a well cut diamonds (regardless of cut, there are some universals about a well cut stone)
- a good relationship with a local jeweler who can check out stones for you for free (test them, confirm your own impressions)
- a local appraiser who can see you and your diamond in a short time frame

As you can see, successful use of these tools really requires a level of familiarity with diamonds and cut quality, color and clarity grading, etc. You need to be somewhat of an expert I think to successfully buy on the secondary market for a good price, since success depends a lot on your own ability to evaluate a diamond. You can buy on the secondary market when you are more of a neophyte if you make sure you have a good long return period and can ship the diamond off to a reliable appraiser (see caveats in my first response though).

 

[GemFever]

Here's a great article on antique stones -- "The Modern Quest for Old Cut Diamonds" by Dave Atlas.

https://www.pricescope.com/journal/modern-quest-old-cut-diamonds

 

[GemFever]

Here's another interesting thread, it has some great pics of a pretty OEC that suffers from some obstruction and lazy facets under the table, but may be a good candidate for a slight recut to fix the problems:

[URL='https://www.pricescope.com/community/threads/old-european-cut-obstruction-and-recut-information-advice.177197/#post-3226508#p3226508']https://www.pricescope.com/community/threads/old-european-cut-obstruction-and-recut-information-advice.177197/#post-3226508#p3226508[/URL]

 

[GemFever]

Another educational thread on how to buy antique diamonds online (with pics and explanations):

Dreamer's Old Cut Guide:

[URL='https://www.pricescope.com/community/threads/dreamers-old-cut-guide.178095/']https://www.pricescope.com/community/threads/dreamers-old-cut-guide.178095/[/URL]

 

[GemFever]

And here's an awesome thread with a bunch of pictures. Looots of pictures

[URL='https://www.pricescope.com/community/threads/old-cut-lovers-please-sign-in.113724/']https://www.pricescope.com/community/threads/old-cut-lovers-please-sign-in.113724/[/URL]

 

[madelise]

lol thanks Gem Fever. I obviously got too lazy to carry out my idea

 

[madelise]

Here's a great thread Mara made with photos comparing an OEC, a tranny and an OMC

https://www.pricescope.com/community/threads/oec-transitional-and-omc-comparison.172376/