Selecting an Ethically Sourced 1CT Marquise Diamond for Your Engagement Puzzle Ring

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Selecting an Ethically Sourced 1CT Marquise Diamond for Your Engagement Puzzle Ring

It’s important to me that you know something about my diamond “worldview” as you approach me for an engagement puzzle ring with a diamond of about 1CT in weight. Here I share with you my thoughts so we can be together in our thinking, and so that – if there is something in particular that you want – you may be explicit in describing it to me as you already know the assumptions under which I make a search for your particular diamond. 

Before going into details about diamonds, I want you to know that we use only ethically sourced diamonds of any size, colored gemstones, and recycled metals from our world-class suppliers. You may read about our Earth-First and Fair Trade vendors here

When I first set out to provide quotes for an engagement ring with a larger diamond, I make certain assumptions. For example, for a diamond that will be worn on a daily basis, I assume that you are not looking for an investment-grade diamond. I could quote you on a 1CT marquise diamond ring with a diamond that’s internally flawless, and prices would start at several times higher than those shown on our site. But that’s not what most – read any – of my clients are looking for. That diamond would, when not set in jewelry, likely be kept in a safe.

Measuring Diamonds by Carat Weight or Millimeter Dimensions
You might ask what is the 1CT range? Great question! Generally, that means a diamond of any weight from 0.90CT to 1.10CT. The 1CT-range diamonds offered by our diamond house are almost always found at weights of 1.0CT to 1.04CT, and if we slide down even a few points to 0.93CT, you may not observe a difference in the visual look.

Diamonds are cut to the size that is best for a particular stone in the estimation of the diamond cutter. So, for example, a 1CT-range diamond will likely be close to 10mm x 5mm, which produces the “ideal for marquise” ratio of 2:1, meaning the length is double the width.

But a 1CT diamond-range stone may vary in the millimeter dimensions. 9.8mm x 5.3mm. 10.5mm x 5mm. It could be 10mm x 5.9mm. Diamonds therefore don’t always demonstrate the much-desired length:width ratio of 2:1. The ratio can vary depending on whether a diamond is cut with a greater or lesser depth. To procure a diamond with the 2:1 ratio or close to it, if desired, it’s necessary to look at the millimeter length and width of a given diamond. (And . . . as a caution . . . to reflect that what is “perfect” for someone else may not make a diamond perfect for you!)

If a diamond weighs 0.90CT and has a length of 10.2mm and a width of 5.25mm, its ratio is 1:94. But note that the millimeter dimensions are greater than 10mm and 5mm, so this diamond will look just as big as a 1CT diamond with the equivalent length and width. This is why we can sometimes, not always, get a 1CT-range marquise diamond that can save you some money by virtue of its slightly lesser carat weight.

Diamond prices rise exponentially with size. This means that a 1 CT diamond is not twice as expensive as a 1/2CT diamond. It may be 5-6 times more costly. So what I like to do is focus on the aspects of diamond quality that make a difference to how beautiful and sparkly it looks on the hand.

Despite what many may tell you, clarity is not the most important diamond characteristic. I think many jewelers like to over-focus on clarity, because they can impress us by showing diamonds with inclusions under different microscope settings. “In this diamond, you can see inclusions under only 10x magnification. But now . . . look at this one! The inclusions are so tiny, it takes 25x magnification for you to see them. This is a great diamond!” Do we really care about that if it’s going to be on her hand every day?

We can save significant money by going down a few steps in clarity, because as long as a diamond has internal flaws (inclusions) that are only visible with a microscope, it doesn’t actually matter how much smaller inclusions are or how many fewer inclusions there are – or even if there are no inclusions – because none are visible to the unaided eye and thereby on the hand.

We can also save some money by sliding a tiny bit in color. The top of the range includes colors D-E-F. Those are known as colorless diamonds. By contrast, diamonds with K-L color are yellow-ish. Our site states that we always provide D-E-F color, and we can do so for you, too, but we can save money if we slide a teensy bit down to G or H color. Those are known as near-colorless diamonds. Typically I only do this for larger diamonds for which the savings is significant or if there is an outstanding smaller diamond with G or H color. And I only do this with full disclosure, discussion, and agreement.

I may go a little overboard on the discussion because unless we had gemological-institute-trained eyes and the proper jewelry examining equipment, you and I couldn’t discern the difference between a G or an H diamond when compared with a D-E-F diamond. So that little change in color doesn’t affect how the diamond looks when she wears it.

There is one other criterion for a beautiful marquise diamond that you won’t hear much about, but I’m picky about this. Some diamonds may have an optical illusion known as bow-tie across the center when looked at from certain angles. It makes the marquise look grayish or black in the shape of a bow-tie, again, only if you see it from the angle at which it shows. Some jewelers say, “Bow-tie gives a marquise diamond character.” I disagree. I think a tiny bit of bow-tie can give a diamond a little character, but we generally seek diamonds with the least evidence of bow-tie possible.

If you want to contact me for individualized quotes for diamonds of 0.90CT or greater, please feel free to email me. My name is Mandira, and I’ll be glad to help you!

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