Are Spread Diamonds a Good Way to Increase Your Engagement Ring Size?

gemologist inspecting spread diamonds

They might sound like something out of Casino Royale or Ocean's 11, but you're more likely to evaluate spread diamonds and diamond spread at the jeweler's case, not the blackjack table. Although they're not as major a consideration as any of the four Cs, if you familiarize yourself with the concepts, you'll be that much closer to finding the perfect loose diamond for the ring of your special someone's dreams.

First, and most importantly: There's a difference between diamond spread and spread diamonds. We’ll break down each of them so you can discuss sparkler size with a gemologist like a pro.

What is diamond spread?

Diamond spread is simply a measure of the table size of a diamond when viewed from the top. (Remember that a diamond's table is the flat facet you see when looking at it head-on — like the top of a table.) It is the size that the diamond appears to be for its given carat weight. A 1ct diamond with a larger spread will seem bigger than a 1ct diamond with a narrower spread, because the reflection (not refraction) may be greater.

What is the ideal diamond spread? It's something to evaluate on a case-by-case basis, depending on a diamond's shape. We've included these measurements in articles about each diamond shape. (For example, the ideal range for the table facet in a round cut diamond is between 54% and 61%. )

If you choose a diamond with spread within those ideal ranges, you'll get a bigger stone with optimal sparkle — without sacrificing brilliance or spending more than you need to. To ensure that you're choosing the ideal diamond spread, work with a gemologist — like one of our on-staff experts — who can tell you about ideal depth and table measurements.

So what are spread diamonds?

A "spread diamond" is generally a shallower diamond. The stone has spread, but at the loss of some depth, which as a result is no longer in the ideal range.

This might seem good, because the stone looks bigger. (The precious diamond material that’s lost from the depth is pushed out in the table. That means the diamond looks bigger across than deeper stones of the same carat weight.) But it can seriously compromise the brilliance of the diamond.

spread diamonds from top and side

Remember that a gem's performance isn't created by a broad table alone — it also relies on depth of the stone. As light passes through a diamond's table, it reflects and refracts off the various facets below. A shallower depth can mean fewer facets, or facets that aren’t angled correctly to bounce the light around optimally, which can mean less sparkle.

How to decide on the right diamond spread

Decide on a diamond by diamond basis. A gemologist, like one of Four Mine's on-staff experts, can help interpret measurements and advise you whether the diamond spread will impact its brilliance.

Are you ready to start shopping? Contact one of our experts today. They can walk you through the features and benefits of any diamond, including its GIA certificate — which lists a diamond's carat size, measurements and ratings on various qualities — so you'll know how to best concentrate your budget.

Not quite ready to talk directly to a gemologist? We're here for you. Fill out the form below to let us know what you're looking for in a diamond and our gemologists will scour through thousands of GIA certified diamonds to find the 3 that best fit your budget and preferences. If you like them, you can start a conversation from there.

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