Look straight down into an Asscher and the stone looks deeper than it is. Concentric steps fall away from a small square table like a staircase seen from the top landing — the effect cutters have called a hall of mirrors for a century. This one is a loose 1.00 carat laboratory grown diamond, D color and VS 1 clarity, 5.58 x 5.53 x 3.56 mm, with Excellent polish and Excellent symmetry recorded on IGI report LG643409805. Nothing is set yet. That is the point.
1.00 Carat
D Color
VS 1 Clarity
IGI LG643409805
Type IIa CVD
Loose Stone
Square emerald cut — the shape the trade calls an Asscher
IGI records the shape and cutting style on this report as SQUARE EMERALD CUT. That is the laboratory’s formal terminology, and it is worth knowing before you read the paperwork, because the trade name for a square step cut with cropped corners is Asscher. Same stone, two vocabularies. The report says square emerald cut; the jewelry world says Asscher.
The measured outline here is 5.58 x 5.53 mm, which is very nearly a true square — five hundredths of a millimeter of difference, invisible to the eye. A step cut arranges long, flat, parallel facets in tiers rather than the many small triangular facets of a brilliant, so the stone trades scintillation for architecture. Instead of sparkle you get depth, breadth, and flashes of white light that arrive in broad planes. It is the Art Deco geometry that made the shape famous in the 1920s and the reason it still reads as deliberate rather than default. If you want to see where it lands as a finished piece, browse Asscher cut engagement rings and its close relative, emerald cut engagement rings.
What D and VS 1 actually mean on a step cut
D is the top of the color scale — the absolute absence of body color, the grade above E and F. VS 1 means very slightly included: inclusions that a trained grader finds under 10x magnification and that you will not find with your eye. Those two grades matter more on this shape than on a round. A brilliant cut breaks light into hundreds of small returns, which busies the eye and hides a faint tint or a small feather. A step cut does the opposite: the long open facets act like windows, so whatever is inside the stone gets shown rather than scrambled. Choosing D and VS 1 for an Asscher is not vanity, it is the grade pairing that keeps a transparent shape looking clean.
The report also records Excellent polish and Excellent symmetry, which on a step cut is the finish detail that keeps the parallel facet rows crisp instead of wandering. Fluorescence is None. IGI does not state a cut grade on this report, and we will not invent one for it. If the grading vocabulary is new to you, our 4Cs of diamonds guide and the complete guide to lab grown diamonds unpack all of it in plain language.
Type IIa, grown by CVD
The comments field on this report reads that the diamond was created by the Chemical Vapor Deposition (CVD) growth process and is Type IIa. CVD builds a diamond layer by atomic layer from a carbon-rich gas inside a reactor. Type IIa is a chemical classification, not a marketing term: it describes diamond with no measurable nitrogen impurity, the same category that includes some of the most famous colorless stones in the world. It is a small, unglamorous line on a report that happens to be one of the better things you can read on one.
A laboratory grown diamond is a real diamond. Same carbon lattice, same 10 on the Mohs scale, same refractive behavior, distinguishable from a mined diamond only by specialist equipment reading its growth signature. It is not a simulant and not an imitation. Our journal covers the how and the why in how lab grown diamonds are made and are lab grown diamonds real diamonds. Because the origin of every stone is documented from reactor to report, these diamonds are conflict-free by construction — more on that in what makes jewelry ethical.
What to build around it
A near-square outline gives a designer a rare amount of freedom. Four cropped corners mean four natural anchor points, so a simple four-prong or a clean bezel both sit on the stone without fighting its geometry — and a bezel in particular echoes the step cut’s straight lines rather than interrupting them. East-west orientation is available on a square stone in a way it never is on a round. Baguette side stones extend the Deco language; a plain knife-edge band lets the stone carry the whole piece.
Aquamarise can set this diamond into a design built around it — the stone is offered as a customizable loose diamond, so a custom mounting is the intended path rather than an afterthought. Start with custom engagement rings, look through solitaire engagement rings and three stone engagement rings for silhouettes, or read how to build a custom engagement ring and engagement ring styles and setting types before you commit. Other loose stones are in loose lab grown diamonds.
Specifications
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Report IGI LG643409805
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Report date July 11, 2024
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Description Laboratory grown diamond
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Shape & cutting style Square emerald cut (trade name: Asscher)
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Measurements 5.58 x 5.53 x 3.56 mm
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Carat weight 1.00 carat
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Color grade D
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Clarity grade VS 1
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Cut grade Not stated on the report
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Polish Excellent
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Symmetry Excellent
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Fluorescence None
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Inscription IGI LG643409805
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Comments Created by Chemical Vapor Deposition (CVD) growth process; Type IIa
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Birthstone April
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Custom setting Available — this stone can be set into a design of your own
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Included Free luxury gift box + free USA shipping
Certification & care
The stone ships with its IGI report LG643409805, issued July 11, 2024, and carries the matching inscription IGI LG643409805 laser-written on the girdle. The number on the paper and the number on the diamond are the same, which is what lets you confirm at any point in the stone’s life that the report in your hand belongs to the diamond in your hand. Report numbers can be looked up directly in IGI’s own online report database. For how IGI grading compares with the other major laboratory, read IGI vs GIA certification, and see our diamond transparency page for how we document what we sell.
Every dimension you need for a mounting is on the report: 5.58 x 5.53 mm across the outline and 3.56 mm deep. Give those three numbers to whoever builds the setting and the head can be made to the stone rather than the stone squeezed into a stock head.
Loose, a diamond is at its safest in the sealed holder or a padded single-stone box, kept away from other stones — a diamond is the only thing hard enough to scratch another diamond, so do not let two of them share a compartment. Cleaning is warm water, a drop of mild dish soap, a soft toothbrush around the pavilion, and a lint-free cloth. Skin oil is what dulls a step cut fastest, and it comes off in under a minute. Our guides to cleaning jewelry at home and caring for your engagement ring cover the routine once the stone is mounted.
Frequently Asked Questions
Is a lab grown diamond a real diamond?
Yes. It is carbon crystallized in the same cubic lattice as a mined diamond, with the same hardness of 10 on the Mohs scale and the same optical properties. IGI grades it on the same color and clarity scales it uses for any diamond. It is not a simulant and not an imitation.
What does the IGI report cover, and how do I verify it?
IGI report LG643409805, issued July 11, 2024, records the description, shape and cutting style, measurements, carat weight, color grade, clarity grade, polish, symmetry, fluorescence, the inscription, and the comments field. The report number can be looked up in IGI’s own online report database, and it matches the number laser-inscribed on the stone.
What is the laser inscription?
The girdle of this diamond carries the microscopic text IGI LG643409805. It is written with a laser, sits on the outer edge where a setting hides it, and is invisible without magnification. Its job is to permanently tie this specific stone to this specific report.
Why does the report say square emerald cut instead of Asscher?
Square emerald cut is IGI’s formal terminology for the shape and cutting style. Asscher is the trade name the jewelry world uses for the same thing: a square step cut with cropped corners. The report wording and the trade wording describe one stone.
What does a D color grade mean?
D is the highest color grade on the scale, meaning no detectable body color. It sits above E and F, which are also considered colorless. On a step cut with long open facets there is nowhere for a faint tint to hide, so the grade is doing real work here rather than sitting on paper.
What does VS 1 clarity mean?
VS 1 stands for very slightly included, grade one. A trained grader locates the inclusions under 10x magnification; the unaided eye does not. On an Asscher, where the wide facets act like windows into the stone, VS 1 is the practical clarity floor for a diamond that reads as clean.
Does the report state a cut grade?
No. This report does not state a cut grade, and we will not assign one it does not carry. What it does record is Excellent polish and Excellent symmetry, which on a step cut is what keeps the parallel facet rows sharp and even.
How does carat weight relate to the millimeter measurements?
Carat is weight, not size. Millimeters are what you actually see. This diamond weighs 1.00 carat and measures 5.58 x 5.53 mm across the outline with a depth of 3.56 mm. When you compare stones, compare the millimeters, because two diamonds of identical carat weight can face up noticeably different depending on how the weight is distributed.
What do Type IIa and CVD mean?
The report comments state that this diamond was created by the Chemical Vapor Deposition growth process and is Type IIa. CVD grows diamond layer by atomic layer from a carbon-rich gas. Type IIa is a chemical classification for diamond with no measurable nitrogen impurity. Because a grown diamond’s origin is documented from reactor to report, it is conflict-free by construction.
Can this stone be set into a ring, and who does the setting?
Yes. This diamond is offered as a customizable loose stone, and Aquamarise can build a piece around it. A jeweler performs the actual setting and the final band sizing, working from the report measurements so the head is made to fit this diamond rather than the other way around. Tell us the style you have in mind and we will take it from there.
Will this stone test as a diamond?
Yes. A standard thermal or electronic diamond tester reads it as diamond, because it is diamond. Distinguishing a laboratory grown diamond from a mined one requires specialist instruments that read growth signatures, which is exactly why the laser inscription and the report exist.
Is a loose lab grown diamond a good investment?
We would rather be honest than promissory: buy it because you want to wear it, not as a financial instrument. Lab grown diamond prices have moved a great deal in recent years and no jeweler can credibly forecast where they go next. Our journal discusses the question openly in the guides on whether lab grown diamonds hold value and whether they are worth it.
Can I have the stone appraised and insured?
Yes, and with a graded loose stone it is straightforward: the IGI report and the matching inscription give an appraiser and an insurer everything they need to identify and value it. Our appraisal page explains the process, and contact us if you need documentation in a particular format.
How does it ship, and what if I need to return it?
The diamond ships free within the USA, insured in transit, packaged in a free luxury gift box with its report. Delivery details are on our shipping page. The policy that applies to a loose stone is set out on our returns and refunds page, so read it there rather than relying on a summary.
How do I clean and store a loose diamond?
Warm water, a drop of mild dish soap, a soft toothbrush, and a lint-free cloth. Skin oil is what dulls a step cut, and it lifts off in a minute. Store the stone in its holder or a padded single-stone box, never loose with other diamonds, since diamond is the only material hard enough to scratch diamond.
