1 Carat Princess Cut Diamond Ring – The Definitive Guide

platinum 1 carat princess cut diamond ring solitaire style

Stunning one carat princess cut diamond solitaire ring from WhiteFlash.com

The princess cut diamond is one of the most popular choice of center stone when it comes to buying an engagement ring. Due to its superior brilliance and unique outline, it’s no wonder that many women prefer the princess diamond over other shapes.

In this write up, I will address some frequently asked questions, show you the important things to look out for and how to save money with a few simple tips when buying a 1 carat princess cut diamond engagement ring.

Here’s a list of topics we will be covering:

How Big is a One Carat Princess Cut Diamond? (Chart Comparison)
How Much Does a 1ct Princess Cut Engagement Ring Costs?
Why Cut Quality Matters in Princess Cut Diamonds
Recommended Guidelines to Shop Smart And Save Money
Top 6 Most Popular Designs for 1 Ct Princess Cut Rings
Final Note: Best Places to Shop for a 1 ct Diamond Ring

How Big is a One Carat Princess Cut Diamond? (Size Chart)

1 karat princess cut diamond ring on size 4 finger

One carat princess cut diamond solitaire ring on a size 4½ finger.

Based on the statistics that were compiled, the average size of a princess cut diamond ring that people buy is 1 carat. In fact, one of the most common questions I get asked is, “How big is a 1ct princess diamond and whether it looks too big/small on a particular finger size.”

Well, a 1ct princess cut diamond that is cut to good proportions will be approximately 5.5mm by 5.5mm in physical size. As a reference, you can use the chart below to get an idea of how big a princess cut diamond is with regards to its carat weight.

princess cut diamond size chart

To download a printable PDF file for carat size comparisons, click here

How Much Does a 1ct Princess Cut Engagement Ring Costs?

It really depends because there are various factors like the 4Cs that would affect the cost of the diamond. As a ballpark figure, I would say that the price of a one carat princess cut diamond with decent color/clarity would be around $6000.

Obviously, this figure could go up or down depending on the specific details of the 4Cs. To illustrate this, check out this price comparison I did based on 3 diamonds with slightly different specifications.

1ct princess cut diamond price comparisons

Note that the final cost of buying an engagement ring would also include the price of the setting. Again, the price of the setting would vary depending on the type and intricacy of the ring design you choose.

So, if you select a setting that costs $1,000, this would put the total estimated cost of the completed ring to be around $7,000.

If you want to get an idea of how much a 1 carat princess cut diamond would cost, head over to JamesAllen.com or WhiteFlash.com and use their listed prices as a benchmark for the specs you are considering.

Why Cut Quality Matters in Princess Cut Diamonds

Cut quality is the most important factor that determines the amount of sparkle or brilliance a princess cut diamond has. Cut is what makes a diamond lively like a disco ball or completely lifeless like frozen spit.

Besides optical performance, poorly cut princess diamonds may run into durability issues and face a higher risk of chipping. This is evident in princess cut diamonds with very thin or extremely thin girdles (avoid!).

So, how do you analyze a princess cut diamond’s cut quality? The main conundrum that consumers have is that the GIA grading reports make no mention of cut grading. The only other reliable lab that does assign a cut grade for princess diamonds is AGS,

While there are general guidelines and proportions that you can follow, the most accurate way to analyze light performance is to use the ASET. In essence, the ASET maps out the interaction of the diamond with light and you can use the following reference charts to determine light performance.

Average – Decent

ags poor princess cut diamond asets

Very Good – Above Average

very well cut princess cut diamonds aset

Ideal – Best

ags000 princess cut aset

Good vendors who care about transparency and want consumers to make educated purchases will make tangible data like the ASET easily available. What about the ones that sell mediocre goods? Well, you guessed it.

The fact is, most vendors won’t provide analytical data because they don’t want you to know what they are really selling. After all, why would they want to jeopardize making money off an unsuspecting consumer by revealing the shortfalls of their goods?

FYI, here’s an example of how a great listing looks like where analytical data is easily accessible.

detailed listing with idealscope and aset

Tangible data like magnified videos, ASET and Idealscope images show you exactly what you are buying.

James Allen, White Flash and Brian Gavin are reliable jewelers who not only provide ASET imagery but also HD videos of their diamonds. This enables you to SEE exactly what you are buying.

Recommended Guidelines to Shop Smart And Save Money

Whether you are buying a princess cut diamond or any other types of diamonds, a reliable grading report from GIA or AGS is mandatory. This ensures that the qualities of the diamond is accurately represented and is a safeguard towards your purchase.

With that in mind, here are my recommended specifications for buying a 1 carat princess cut diamond ring:

Cut: Ideal (refer to ASET images above)
Color: G or better (faces up icy white)
Clarity: SI1 or better (as long as eyeclean)

The reasoning behind these specifications can be summed up in one word: practicality. This combination enables you to get the best value for your money without the need to spend on features that your eyes cannot see.

Take a look at the comparison below and you’ll see what I mean.

g vs2 versus d vvs2 prices

While both diamonds will look identical in the face up view, there is a whopping 30% price differences between them! On top of that, the G VS2 diamond is arguably better in terms of light performance.

Now, if you are not color sensitive or don’t mind seeing a slight tinge of color in the engagement ring, you may even want to consider going down to an I or J color to enjoy a bigger discount.

At the end of the day, cut is KING. The other aspects of the 4Cs are largely up to personal preferences and individual tastes.

James Allen, White Flash and Brian Gavin are recommended vendors for ideal cut princess diamonds. If you are looking for a bright and brilliant stone, check out their signature diamonds first.

Top 6 Most Popular Designs for 1 Ct Princess Cut Rings

Princess cut diamonds are quite versatile and generally look better when set in white gold or platinum settings. One of the things to take note when selecting a ring design is to ensure that the 4 sharp corners are adequately protected to prevent chipping.

Here are 6 of the most popular 1 carat princess cut diamond ring designs that will make her say “YES!”. If you are interested to see more details of the ring, simply click on the corresponding images…

simple 4 prong 14k solitaire princess cut engagement rings 1 carat
split shank halo princess diamond ring

legato micro pave one karat princess cut engagement ring
18ct white gold one carat princess cut diamond ring flush fit

3 stone princess cut diamond ring with 1 karat center stone
verragio designer princess cut diamond ring

If you need more ideas and design inspirations for a 1 carat princess cut ring, check out this gallery of previously purchased jewelry. You can literally browse through 1000s of real-life rings that customers have bought.

design inspiration ring ideas with princess cut diamonds

Final Note: Best Places to Shop for a 1 ct Princess Diamond Ring

Regardless of where you prefer to shop for your diamond ring, I’m a strong advocate of making purchase decisions based on tangible data and scientific facts. And when it comes to light performance and ideal cut quality, there are only a few places in the world that offer high quality princess cut diamonds.

In my opinion, the best places to shop for a 1 carat princess cut diamond engagement ring are White Flash, Brian Gavin and James Allen. All 3 vendors specialize in super ideal cut princess diamonds and offer exemplary customer service.

More importantly, they have transparent business practices and the consumer’s interest at heart. So, if you are looking for top notch quality jewelry and want to take the guesswork out of buying an engagement ring, make sure you check them out!

With that, I hope you found the insights in this article useful and if you have questions, feel free to get in touch.

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  1. Paul Gian-
    July 24, 2016 at 8:41 am

    Here’s a case study analysis that was performed on a 1 carat princess cut diamond from Brian Gavin Diamonds.

    Brian Gavin Signature 1.058 G VVS1 Signature Princess

    upclose view of 1 carat princess cut diamond

    This diamond is one of the few princess cuts on the market today that is able to meet the AGS 0 cut standards for light performance. Here’s a quick trivia: did you know that more than 80% of the world’s princess cuts won’t even make it to an AGS cut grade of 2?

    The ugly truth is, the majority of diamond are cut to terrible proportions and performance. In fact, it is estimated that only 2-3% of them would make the strict criteria for a 0 cut-grading. Before we delve deeper in light performance analysis, check out the specifications of stone below…

    Shape: Square Modified Brilliant Table %: 62.8
    Grading Report: AGS Depth %: 75.3
    Carat: 1.058 Crown %: 13.9
    Color: G Crown Angle: 40.5
    Clarity: VVS1 Star %: –
    Measurements: 5.47 X 5.46 X 4.11 Pavilion Angle: 39.1
    Lab Cut Grade: Ideal Pavilion %: 57.5
    Light Performance: Ideal Culet: Pointed
    Polish: Ideal Fluorescence: Negligible
    Symmetry: Ideal Girdle: Thin Faceted

    Next, things get interesting when we review the scope analysis for the diamond’s optical performance.

    idealscope for princess cut

    Saturated reds in Idealscopes are great!

    This Idealscope image shows a nice even red color which indicates a super bright diamond. The white and black portions indicate light leakage and contrast respectively. In this particular diamond, the blacks are nicely distributed throughout the entire diamond and creates a visually appealing stone that scintillates with an awesome contrast.

    ideal princess cut diamond aset image

    Superb light return indicated by ASET image

    One of the issues most princess cuts have is that most do not scintillate well. Personally, I love diamonds that show more contrast (blues in ASET or blacks in idealscope). This will prevent the diamond from looking like a block of crushed ice on your finger.

    Besides having a nice distribution of blacks in the ASET, today’s princess cut diamond has a nice edge to edge brightness in it. The reds on the ASET extend all the way to the 4 corners of the stone and it has TONS of red as compared to other ideal cut princess diamonds.

    line up of 3 AGS 000 princess cut diamonds

    Comparison of 3 AGS 0 ideal cut princesses

    See how the first stone stand out in terms of light return from other AGS 0 princess cut diamonds?

    A Truly One of Its Kind in the World of Princess Cuts…

    For a princess cut diamond that is sitting right at the pinnacle of cut and light performance, the tag on this 1 carat baby is only $8,085. While it may be slightly more expensive (due to more diamond waste during the cutting process to achieve superior cut grade) than any other “unbranded” poorly cut princesses you might see on the market, it is well worth it.

    This is the reason why Brian Gavin’s signature diamonds are highly sought after. So, if you are looking for a stone with maximum brilliance and sparkle, look no further.

  2. Luke-
    December 2, 2018 at 4:59 am

    I was wondering what does a 1 carat princess cut diamond look like and came across your chart. Very useful! Do you have similar reference charts or tables for 1 carat princess cut diamond prices? Similar to that offered by Rapaport pricing?

  3. Paul Gian-
    December 4, 2018 at 7:55 pm

    I don’t have such a price chart for reference and the thing is, it won’t be accurate as well. Rapaport lists diamonds on the HIGH side which is somewhat unrealistic when it comes to online vendors. With high end vendors, it’s unrealistic as well because they are going to charge way higher than Rapaport prices because of their brand premiums. And the thing is, you may not even be getting a high quality diamond when buying at high street. I’ve outlined a process to compare prices in this article. The best way to compare prices of 1 carat princess cut diamonds is to head over to James Allen and use the filter to narrow down the range of color/clarity you are looking at. These are REAL time prices that are as competitive as it gets. For example, I would expect retail prices to be about 20% higher than JA prices and that should give you a rough idea about what you are paying for.

  4. Sarah-
    October 12, 2019 at 9:04 am

    I have size 7 fingers and relatively large hands and I want to find out how the different carat sizes of princess cut engagement rings on finger will look like. What carat size would you recommend so that it is just right in proportion to the size of my hands?

  5. Paul Gian-
    October 14, 2019 at 5:02 am

    My wife is a size 7 as well and I’ve previously bought a 0.6ct princess cut diamond ring for her. You can refer to the images here. For a size 7 finger, I find that a 1 carat size diamond would look great. If that is over your budget, you can consider buying a smaller carat size diamond and mounting it in a halo setting to compensate for a larger looking ring. That would work well too!

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