shape
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CHECKLIST - Questions to Ask BEFORE Purchasing a Diamond

D_

Shiny_Rock
Joined
Apr 14, 2015
Messages
245
Hi All,

I love building checklists, find it helpful when there are so many factors to consider, like when buying diamonds.
Below are what I have managed to pool from different resources and threads.
The simple way, as discussed in another thread is: ideal proportions -> HCA <= 2? If yes, get IS & ASET images? If they look good, done.
Maybe this is nitpicking, but I find asking (at least some) of these questions BEFORE purchase helpful (or better still, during the selection process, to whittle down some before badgering the ever so patient sales associates).
It minimizes buyer's remorse and better than finding our self second-guessing our choice and thought about these AFTER the fact (or worse, after the return window has expired).
And my understanding is, no matter how simple the process is, both consumers and vendors would like to avoid returns/exchanges.

Would appreciate additional inputs.
What did I miss?
Which ones do you think "wow, you're cray, you don't really need to know that"

Note: this list is built for MRBs. If others can include checklist for other shapes, that'd be great!

General
Is it GIA/AGS certified?

Cut/Specs
Depth: 60 – 62%
Table: 53 – 58%
Crown: 34.0 – 35.0 degrees
Pavilion: 40.6 – 41.0 degrees
(Complementary crown and pavilion angles if possible)
Lower Girdle: 76 – 80%
Girdle: Thin to Slightly Thick
Culet: None or Pointed
- Are there significant variances between the minimum and maximum angles?
- Are there significant impact from azimuth shifts?

Carat
Is the diamond of the right size for its weight/carat?

Clarity
- Is it eye clean?
- What is the vendor's definition of eye clean versus our definition? e.g. Is it clean when viewed from the pavilion? Viewing distance? (Note: normal human eyes cannot focus, much less see tiny inclusions, on objects held closer than 6 inches)
- Location(s) of the inclusions? crown/pavilion/girdle? Are they dead centre/can be covered by the settings (prong-able)?
- Size of the inclusions?
- What is the colour of the inclusions (crystal, cloud etc.)? Carbon (black), white, brown etc.?
- Are there surface breaching inclusions? If so, are they open or healed?
- Does any of the inclusion pose durability issue to the diamond? (esp. if they are near the girdle)
- Does it have red flags? e.g. clarity grade is based on clouds not shown, additional clouds and/or surface graining not shown (esp. for lower clarity levels, SI1 and below)

Colour
- Does it face up white?
- How does it look seen from the pavilion?
- What colour is the diamond's hue? Yellow/brown/grey/other colour?

Fluorescence
- Does it have fluorescence?
- Does the fluorescence make the diamond look milky/hazy?
- What is the colour of the fluorescence?
- Does the fluorescence help to make the diamond appear whiter or the presence of flurescence actually caused the diamond to be misgraded upward?

Light performance:
- Are there light leakages present observed from the Ideal Scope and ASET images?
- How significant are the light leakages for the size I am considering?
- Are there any signs of painting and/or digging? To what degree? Will that have noticeable impact on the light performance of the diamond?

Cost
Is it priced fairly? (Do price comparisons with diamonds with simlar specs from other vendors)

Setting
- Ring size
- Metal choice?
- Effect on diamond colour? (makes it faces up whiter, makes the yellow tint less visible)
- Does the setting mostly cover the side view or does it have an open gallery?
- Does it allow for maximum light entry?
- Is it too thin/thick considering finger & diamond size?
- Is it structurally sound?
- Is it practical? (Consider lifestyle, occupation type etc.)
- # of prongs + pros & cons?

Policies
Limitations, length they are good for, etc. on:
- Trade-up
- Buyback
- Return
- Shipping
 

diamondseeker2006

Super_Ideal_Rock
Premium
Joined
Jan 11, 2006
Messages
58,547
If you stick to XXX HCA below 2, and depth no greater than 62.3, you won't end up with a stone that faces up too small for it's weight. A lot is accomplished by sticking to the parameters that yield the good HCA score.

I would just add, run it by us before you buy. Do NOT be pressured to buy right then. Pressure is a red flag to me about the vendor.

You will likely not find a local jeweler who will do an idealscope or ASET image, just so you know. You'd have to stick to PS vendors to have a chance for that. And that is why most of us who have been around here for awhile only buy from vendors who provide it.
 

D_

Shiny_Rock
Joined
Apr 14, 2015
Messages
245
Thanks, Garry.
What are the angles that will still be safe?
Or as long as they yield HCA <= 2 like DS said?
I do remember you saying that minor light leakage on smaller stones won't be too noticeable.

DS, you're right abt IS, ASET and local vendors. I went to a couple stores asking if they have any of them and they gave me that :confused: look.
But then again if we are able to see the diamonds with our own eyes, do we still need them?
Granted the store lighting can skew our perspectives.
I remember in one of his experiments, Rhino says that we shouldn't discount our eyes (the diamond that has worse ASET image doesn't necessarily look worse irl).
 

tyty333

Super_Ideal_Rock
Premium
Joined
Dec 17, 2008
Messages
27,198
Nice check list.

Isnt lower girdle suppose to be 75% instead of 76%?
 

solgen

Brilliant_Rock
Joined
Apr 10, 2015
Messages
563
Here's what I typically use for cut/specs on MBC.

Depth can go to 62.6% IMO. You might lose a little face up size. On searches I'll typically use a 60-63% range.
Crown angle 33.0-36.0 (typically 34-35 is my sweet spot)
Pavilion can range from 40.3-41.6. (40.5-40.8 is my ideal range)
Table 52-60 (I prefer 55-57)
LGF is 75-80% but GIA rounds the figure so kinda pointless(77% ideal for me)
Star facet 40-55

LGF and table size effect the thickness of the arrows pattern so if you like them thicker the shorter LGF and smaller table help.
 

Rhino

Ideal_Rock
Trade
Joined
Mar 28, 2001
Messages
6,340
D_|1439053867|3912523 said:
Thanks, Garry.
What are the angles that will still be safe?
Or as long as they yield HCA <= 2 like DS said?
I do remember you saying that minor light leakage on smaller stones won't be too noticeable.

DS, you're right abt IS, ASET and local vendors. I went to a couple stores asking if they have any of them and they gave me that :confused: look.
But then again if we are able to see the diamonds with our own eyes, do we still need them?
Granted the store lighting can skew our perspectives.
I remember in one of his experiments, Rhino says that we shouldn't discount our eyes (the diamond that has worse ASET image doesn't necessarily look worse irl).

You shouldn't discount your eyes but what is important when using your eyes is having a "standard" to which you are comparing to. There are many consumers who will trust their eyes and then walk into a jewelry store that shows them a series of leaky diamonds. If the standard is then "leaky" diamonds it's a matter of picking that which has the least leakage but if there is not way to judge what the standard is can make it a more difficult comparison. Food for thought. There are some other questions we like answered as well but you've got a decent checklist there.

All the best,
Rhino
 

Rockdiamond

Ideal_Rock
Trade
Joined
Jan 7, 2009
Messages
9,711
My preferences are a bit different- but one point I do think is important is LGF- This is one of the stats where a 5% difference will produce a big difference in the personality of the diamond.
I like the shafts thinner, so 80% is my personal sweet spot.
Especially combined with the slightly larger 60% table. slightly spreadier 60% depth, CA 34%/PA 40.5%.
Again, personal sweet spot. Honestly you don't find this combo all that often.
It's like the polar opposite of H&A in terms of the way it handles the light.

Rhino makes a great point.
Now that you've learned more, actual hands on experience will prove to be very valuable.
If you can get to a stone that carries AGSL graded stones, you're likely to see some well cut stones.
 

D_

Shiny_Rock
Joined
Apr 14, 2015
Messages
245
Rhino|1439065515|3912549 said:
D_|1439053867|3912523 said:
Thanks, Garry.
What are the angles that will still be safe?
Or as long as they yield HCA <= 2 like DS said?
I do remember you saying that minor light leakage on smaller stones won't be too noticeable.

DS, you're right abt IS, ASET and local vendors. I went to a couple stores asking if they have any of them and they gave me that :confused: look.
But then again if we are able to see the diamonds with our own eyes, do we still need them?
Granted the store lighting can skew our perspectives.
I remember in one of his experiments, Rhino says that we shouldn't discount our eyes (the diamond that has worse ASET image doesn't necessarily look worse irl).

You shouldn't discount your eyes but what is important when using your eyes is having a "standard" to which you are comparing to. There are many consumers who will trust their eyes and then walk into a jewelry store that shows them a series of leaky diamonds. If the standard is then "leaky" diamonds it's a matter of picking that which has the least leakage but if there is not way to judge what the standard is can make it a more difficult comparison. Food for thought. There are some other questions we like answered as well but you've got a decent checklist there.

All the best,
Rhino

Thanks, Rhino!
I find your videos very useful and the closest thing we can get w/o having to go to local vendors and compare some diamonds irl. Not to mention looking for a few diamonds to make useful comparison is not always an easy task!
The article/experiment I was referring to earlier is the GIA Ex vs. AGS Ideal http://www.goodoldgold.com/gia_ags_ideal_consumers.jsp, but I guess there was the painted girdle issue that needed to be taken into account as well.

Rockdiamond, do diamonds w/ the angle combo in your personal sweet spot behave differently from 60/60 diamonds in general (which I understand are different from ideal H&A diamonds)?
 

Rockdiamond

Ideal_Rock
Trade
Joined
Jan 7, 2009
Messages
9,711
Hi D,
In general- the more important number in changing the personality is the LGF, combined with table depth changes.
In some ways, the slightly larger table is offers compensation for the shallower CA in a different kind of brilliance.
A lot of what we're discussing is very subtle and has been brought up- the eyes really need to be the determining factor.
I very much admire the the thought effort and technology behind the HCA. It does what it was designed to do. I advise consumers to consider a broad range of aspects of the four C's - including HCA. There's cases where specific HCA is less relevant to my overall decision making.
I was offered a 6ct K/SI2 diamond once- triple EX.
The stone looked amazing in real life- I mean six carats is a big diamond.
Plus the grade made the stone desirable from a price standpoint ( cheap).
It was pretty much eye clean, and faced up white.
60.7d
60T
33 CA
41.2PA
It scored over 2.7 on HCA- which one could easily take as some sort of a diss based on a lot of what's written. Stay away from stones scoring over 2 is a common suggestion- I don't know if Garry would even agree with that, as a blanket statement.
Now, it wasn't like I could simply find another 6ct K/SI2 triple EX that scored better.......
And as mentioned, a lot of what we're speaking of is subtle.
Looking at the stone in person I did not feel like I was giving up anything from a visual standpoint.
The 80%LGF combined with the size, and more generous table made the stone have tons of sparkle.
In person, if you compared two stones, you might actually pick a stone that scores higher on HCA- or that has as ASET that implies it's not cut as well due to it's in person personality.
In person buying really is different than internet buying in this regard.
If a person is shopping for a 1ct G/SI1 RBC, where there's 1000 candidates, it's a different story than if one is shopping a 2ct diamond - and as we get larger there's less candidates to choose from.
 

D_

Shiny_Rock
Joined
Apr 14, 2015
Messages
245
That's fascinating, Rockdiamond.
Thanks for sharing!

I agree, it's a different experience.
And herein lies the problem.
I can't exactly walk to a store and ask them to take out all of their inventory in the range of .9 - 1C, G-H, VS2-S12 so I can look at which one that "speaks" to me/which personality I like best, can I?
Easier to do w/ larger carats (2+) because of less amt to select from and higher amt of $$$ for the vendor to make it worthwhile to do so.
 

Rhino

Ideal_Rock
Trade
Joined
Mar 28, 2001
Messages
6,340
D_|1439081009|3912626 said:
Rhino|1439065515|3912549 said:
D_|1439053867|3912523 said:
Thanks, Garry.
What are the angles that will still be safe?
Or as long as they yield HCA <= 2 like DS said?
I do remember you saying that minor light leakage on smaller stones won't be too noticeable.

DS, you're right abt IS, ASET and local vendors. I went to a couple stores asking if they have any of them and they gave me that :confused: look.
But then again if we are able to see the diamonds with our own eyes, do we still need them?
Granted the store lighting can skew our perspectives.
I remember in one of his experiments, Rhino says that we shouldn't discount our eyes (the diamond that has worse ASET image doesn't necessarily look worse irl).

You shouldn't discount your eyes but what is important when using your eyes is having a "standard" to which you are comparing to. There are many consumers who will trust their eyes and then walk into a jewelry store that shows them a series of leaky diamonds. If the standard is then "leaky" diamonds it's a matter of picking that which has the least leakage but if there is not way to judge what the standard is can make it a more difficult comparison. Food for thought. There are some other questions we like answered as well but you've got a decent checklist there.

All the best,
Rhino

Thanks, Rhino!
I find your videos very useful and the closest thing we can get w/o having to go to local vendors and compare some diamonds irl. Not to mention looking for a few diamonds to make useful comparison is not always an easy task!
The article/experiment I was referring to earlier is the GIA Ex vs. AGS Ideal http://www.goodoldgold.com/gia_ags_ideal_consumers.jsp, but I guess there was the painted girdle issue that needed to be taken into account as well.

Rockdiamond, do diamonds w/ the angle combo in your personal sweet spot behave differently from 60/60 diamonds in general (which I understand are different from ideal H&A diamonds)?

This is true D. Where are you from if it's ok to ask?
 

Rhino

Ideal_Rock
Trade
Joined
Mar 28, 2001
Messages
6,340
Rockdiamond|1439087597|3912647 said:
Hi D,
In general- the more important number in changing the personality is the LGF, combined with table depth changes.
In some ways, the slightly larger table is offers compensation for the shallower CA in a different kind of brilliance.
A lot of what we're discussing is very subtle and has been brought up- the eyes really need to be the determining factor.
I very much admire the the thought effort and technology behind the HCA. It does what it was designed to do. I advise consumers to consider a broad range of aspects of the four C's - including HCA. There's cases where specific HCA is less relevant to my overall decision making.
I was offered a 6ct K/SI2 diamond once- triple EX.
The stone looked amazing in real life- I mean six carats is a big diamond.
Plus the grade made the stone desirable from a price standpoint ( cheap).
It was pretty much eye clean, and faced up white.
60.7d
60T
33 CA
41.2PA
It scored over 2.7 on HCA- which one could easily take as some sort of a diss based on a lot of what's written. Stay away from stones scoring over 2 is a common suggestion- I don't know if Garry would even agree with that, as a blanket statement.
Now, it wasn't like I could simply find another 6ct K/SI2 triple EX that scored better.......
And as mentioned, a lot of what we're speaking of is subtle.
Looking at the stone in person I did not feel like I was giving up anything from a visual standpoint.
The 80%LGF combined with the size, and more generous table made the stone have tons of sparkle.
In person, if you compared two stones, you might actually pick a stone that scores higher on HCA- or that has as ASET that implies it's not cut as well due to it's in person personality.
In person buying really is different than internet buying in this regard.
If a person is shopping for a 1ct G/SI1 RBC, where there's 1000 candidates, it's a different story than if one is shopping a 2ct diamond - and as we get larger there's less candidates to choose from.

Absolutely on the lower halves. After the pavilion mains I consider them the most important facet set in determining personality and I too like the 80% range and have in the past purposely had diamonds cut past that up closer to 85%. :angel:
 

D_

Shiny_Rock
Joined
Apr 14, 2015
Messages
245
From somewhere in Asia, Rhino :)
 

solgen

Brilliant_Rock
Joined
Apr 10, 2015
Messages
563
Rhino|1439134988|3912724 said:
Absolutely on the lower halves. After the pavilion mains I consider them the most important facet set in determining personality and I too like the 80% range and have in the past purposely had diamonds cut past that up closer to 85%. :angel:

That could make for an interesting video comparison though sometimes videos don't adequately capture the small nuances. Larger table and longer lowers affecting the appearance of a diamond. Effect of varying crown angles too.
 

Rockdiamond

Ideal_Rock
Trade
Joined
Jan 7, 2009
Messages
9,711
D_ said:
That's fascinating, Rockdiamond.
Thanks for sharing!

I agree, it's a different experience.
And herein lies the problem.
I can't exactly walk to a store and ask them to take out all of their inventory in the range of .9 - 1C, G-H, VS2-S12 so I can look at which one that "speaks" to me/which personality I like best, can I?
Easier to do w/ larger carats (2+) because of less amt to select from and higher amt of $$$ for the vendor to make it worthwhile to do so.

D- you absolutely CAN walk in and ask to see every stone.
The store can say no, but if you are actually in the market, and let them know, any smart merchant will be very glad to take the time to show you some or all of what they have.
If they have diamonds, but won't take the time to show them to you, it's hard to imagine how they'd stay in business very long.
Remember- it's YOU who's doing them the service by considering them as a merchant.

Nice to know we both love 80%'ers Rhino!
I have seen some of the variations with the super long (85%) LGF's - really nice!
Outside my personal faves, but also a very cool look.

solgen said:
Rhino|1439134988|3912724 said:
Absolutely on the lower halves. After the pavilion mains I consider them the most important facet set in determining personality and I too like the 80% range and have in the past purposely had diamonds cut past that up closer to 85%. :angel:

That could make for an interesting video comparison though sometimes videos don't adequately capture the small nuances. Larger table and longer lowers affecting the appearance of a diamond. Effect of varying crown angles too.

It's actually easier to capture differences in LGF in video/pictures than some differences on CA/PA

POL/Symmetry differences from G-EX are all but impossible to capture......changing the LGF's really has the most dramatic effect.
 

D_

Shiny_Rock
Joined
Apr 14, 2015
Messages
245
Rockdiamond|1439146076|3912773 said:
D- you absolutely CAN walk in and ask to see every stone.
The store can say no, but if you are actually in the market, and let them know, any smart merchant will be very glad to take the time to show you some or all of what they have.
If they have diamonds, but won't take the time to show them to you, it's hard to imagine how they'd stay in business very long.
Remember- it's YOU who's doing them the service by considering them as a merchant.

Thanks, never thought about it that way.
One of the important reason I like to buy online is that I can browse without feeling that I'm being too imposing.
(and I don't browse unless I'm in the market, or helping others to look for one, otherwise that'll be a recipe for impulse purchases).
Though in person shopping and being able to see the diamonds on my own is a lot of fun!
 

Rhino

Ideal_Rock
Trade
Joined
Mar 28, 2001
Messages
6,340
solgen|1439142662|3912755 said:
Rhino|1439134988|3912724 said:
Absolutely on the lower halves. After the pavilion mains I consider them the most important facet set in determining personality and I too like the 80% range and have in the past purposely had diamonds cut past that up closer to 85%. :angel:

That could make for an interesting video comparison though sometimes videos don't adequately capture the small nuances. Larger table and longer lowers affecting the appearance of a diamond. Effect of varying crown angles too.

Search "lower half facets" on YT. You'll pull up some vids.
 

Karl_K

Super_Ideal_Rock
Trade
Joined
Aug 4, 2008
Messages
14,634
I have had stores that showed me nearly every diamond in the place even when they knew I was not buying right then. The key was going in when it is real slow and talking to the owner/manager and let them know your willing to step aside if a paying customer comes in.
One owner even left out 6 1ct diamonds in front of me and went off to help someone across the store.
We played with all the toys the microscope, loupes and the Ideal scope I brought in.
After a couple hours I got a call and had to go and he invited me back anytime saying it was the most fun he had in a long time at work.
At another a while later we looked at every diamond in the place under an ASET scope I brought in over several hours.

I have had others where when I had money in my pocket they were grumpy about even showing me 2 or 3 even when it was real slow.
I just left and visited the next one down the street.
The real difference was some are salesman who happen to sell diamonds and others are diamond enthusiasts who sell diamonds.
When you find one of the later it can be a whole lot of fun and they are not all that rare in the industry.
 

D_

Shiny_Rock
Joined
Apr 14, 2015
Messages
245
Karl_K|1439307042|3913322 said:
The real difference was some are salesman who happen to sell diamonds and others are diamond enthusiasts who sell diamonds.

So true, Karl.
That's why I had a couple of stores telling me that a VS2 "will look yellow" and suggested me to go for VVS1s instead :wall:
 

Rockinruby

Ideal_Rock
Joined
Dec 27, 2013
Messages
2,740
This has some helpful info!
 
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