SI1 vs SI2 diamond clarity compares two slightly included grades, with SI1 usually offering better eye-clean potential and SI2 requiring closer inspection.
How this entry was checked: facts are tied to a linked source or to our verified data sets; retailers are scored on the same published criteria. Pricing data provided by Rare Carat from its inventory feed, updated November 12, 2026. Other retailers' prices were verified September 22, 2026.
SI1 vs SI2 diamond clarity compares two grades in which inclusions are noticeable under 10x magnification. SI1 usually has a higher chance of appearing eye-clean. SI2 can offer lower pricing, but inclusion position, size, color and cut determine visible appearance.
SI1 vs SI2 diamond clarity compares two slightly included grades on the standard diamond clarity scale, with SI1 generally offering greater eye-clean potential and SI2 requiring closer inspection of the individual stone.
Every fact in this entry is tied to a linked source or to our verified data sets, and every retailer named is scored on the same published criteria.
GIA and IGI use clarity grades to describe internal inclusions and external blemishes observed under 10x magnification by trained graders. SI means Slightly Included. The scale places SI1 above SI2, but it does not predict exactly what a buyer will see without magnification. Two diamonds with the same grade can have different inclusion types, locations and visual effects.
The phrase SI1 and SI2 clarity describes a grade range, not a guarantee of appearance. These slightly included diamond grades can contain inclusions with very different effects on face-up appearance. An inclusion under the table can be easier to see than one near the girdle. A dark crystal can attract attention sooner than a transparent feather. A cloudy group of inclusions can reduce transparency across a larger area. Cut quality also affects how reflections hide or reveal internal features.
SI1 usually has a better chance of appearing clean to the unaided eye than SI2. That statement describes probability, not a fixed result. Some SI1 diamonds show a visible crystal, feather or cloud. Some SI2 diamonds look clean from the normal distance used to view a ring.
The location of an inclusion often matters more than its presence. A feature below the table can sit in the main viewing area. A feature near the girdle may be less apparent, especially under a prong. A surface-reaching feather can be visible from the side or can raise a durability concern if it reaches a vulnerable edge.
The diamond’s shape changes the inspection standard. Step-cut shapes such as emerald and Asscher cuts have broad, open facets that can make inclusions easier to see. Brilliant cuts create more visual activity and can hide some inclusions. Use the guides to diamond clarity grades and diamond shape together rather than treating clarity as an isolated specification.
A higher clarity grade generally commands a higher price when the other characteristics are similar. The difference between SI1 and SI2 is not uniform. It changes with carat weight, shape, cut, color, laboratory report and the visibility of the inclusion.
A buyer comparing SI1 versus SI2 diamonds should inspect the actual stones rather than assume that the grade difference predicts the entire price difference. A clean-looking SI2 can offer useful value when the inclusion is difficult to see and does not affect durability. An SI1 with a prominent dark mark may deserve less consideration than a lower-graded stone with a cleaner face-up appearance. The report grade still matters, but the video and direct inspection provide information the grade cannot provide alone.
Compare diamonds with the same shape, approximate carat weight, color, cut grade and laboratory report before judging the clarity price. A one-grade difference does not explain every price difference between listings.
Most inclusions do not make a diamond unsafe to wear. The type and position of a feature require attention. A feather that reaches the girdle, a cavity at the edge or a large surface-reaching break may be more important than a small internal crystal under the table.
Ask the retailer to identify any durability concern in writing. Inspect the girdle and pavilion views. Prongs can cover a small edge feature, but a setting does not remove the underlying characteristic.
The diamond’s mounting also affects daily risk. A bezel setting offers different edge coverage from a prong setting. Metal choice and construction matter as well, so review the best metal for daily wear before selecting a low-clarity diamond for constant use.
Clarity grade affects how a future buyer evaluates a diamond, but it does not determine resale value by itself. Buyers commonly prefer a certified stone with attractive face-up appearance, sound durability and a desirable shape. A visibly included SI2 can have a narrower buyer pool than a clean-looking SI1.
Retail purchase price and later resale price are different measures. The original setting, retail margin, report, market demand and condition can all affect a later offer. Keep the grading report, invoice and any service records. These documents help establish identity and specifications.
Start with the grading report. Confirm the laboratory, report number, shape, measurements, carat weight, color, clarity and cut information. Then match the report to the actual diamond. A diamond grading report is a record of characteristics, not a substitute for viewing the stone.
The table below identifies the main checks.
| What to look at | What good looks like | Red flag |
|---|---|---|
| Clarity grade field | The report clearly states SI1 or SI2, with the laboratory and report number visible. | The listing uses a clarity term without showing a report or identifying the laboratory. |
| Inclusion plot | The plot gives a useful map of the inclusion type and approximate position. | The plot is missing, unreadable or inconsistent with the listing. |
| Table area | The center of the diamond appears clean at normal viewing distance and under ordinary lighting. | A dark crystal, obvious feather or cloudy patch remains visible without magnification. |
| Pavilion and side view | The diamond remains attractive from the side, with no prominent feature affecting transparency. | A dark inclusion is visible through the pavilion or a break reaches the girdle. |
| Inclusion color | Pale or transparent features have limited contrast against the diamond. | A black or strongly contrasting feature draws the eye immediately. |
| Inclusion position | An edge feature is distant from vulnerable points and may be covered by a secure setting. | A cavity, feather or break sits on the girdle or near a pointed shape corner. |
| Cut performance | The diamond returns light evenly, with strong brightness and no persistent dull area. | Poor light return makes inclusions and transparent areas easier to see. |
| Magnified video | The video helps identify the feature while showing the stone from several angles. | The listing shows only a stock image or avoids a view of the inclusion. |
| Laser inscription | The inscription matches the report number under magnification. | The inscription is absent, unreadable or does not match the report. |
| Shape-specific risk | The inspection standard matches the shape. Step cuts receive a stricter clarity review than many brilliant cuts. | A seller applies the same eye-clean claim to every shape and size. |
A retailer may use the term eye-clean to describe a visual result, but the term is not a laboratory grade. Ask how the retailer defines it and from what distance the assessment is made. A claim based only on magnified inspection does not answer the question a ring buyer is asking.
View the diamond face-up first. Hold it at the distance used for ordinary conversation and ring inspection. Then move it under diffuse indoor light, direct light and daylight. Rotate the stone slowly. A feature that disappears in one position may appear in another.
The most important test is not whether an inclusion can be found at 10x magnification. The report already records that. The practical test is whether the feature attracts attention during normal wear.
Magnification remains useful. It helps identify the feature described on the report, separates a crystal from a feather and reveals surface-reaching characteristics. Rare Carat states that in-house Rare Carat Qualified Staff members inspect the laser inscription and grading certificate at 60x-110x magnification at its New York/New Jersey facilities. That inspection supports identity and documentation. It does not change the laboratory clarity grade.
Cut controls brightness, contrast and scintillation. A well-proportioned diamond can disguise some inclusions through repeated light and dark reflections. A poorly performing diamond can leave inclusions exposed in a dull or transparent area.
Use the diamond cut grade guide to understand the report’s cut information. For round diamonds, GIA cut grades are especially useful. Fancy shapes do not receive the same overall cut-grade system from GIA, so inspect the actual stone with greater care.
Carat weight also changes visual scale. Read carat weight versus size before comparing a larger SI2 with a smaller SI1. A larger stone may show the same inclusion more clearly because the feature occupies more visible area.
Inclusion visibility depends partly on contrast with the diamond. Dark inclusions are often easier to see than pale inclusions. Body color can also affect the overall impression. A buyer comparing clarity should hold color, cut and shape as constant as possible.
Do not assume that a higher color grade solves a clarity problem. Review the stone as a whole. The diamond color grades guide explains why body color and face-up appearance do not always correspond in the same way across shapes.
The grade gives a standardized clarity description under specified conditions. It does not promise that a diamond is clean to the eye, and it does not identify the feature that matters most to a particular buyer.
A listing can accurately state SI1 and still show a visible inclusion. A listing can accurately state SI2 and still show a clean face-up diamond. Inspect the actual stone.
A grade label compresses several observations into one term. The inclusion type, number, size, relief and location remain important. A single dark crystal can matter more visually than several faint clouds.
Read the inclusion plot and comments. Ask for a direct explanation if the plot is difficult to interpret. Do not infer appearance from the grade alone.
Lower clarity can reduce cost, but a low price does not compensate for a risky girdle or damaged edge. Pointed shapes need special attention at their corners. Emerald cuts need careful review of the open table. Halo and prong settings should not be treated as protection against every structural concern.
GIA and IGI are established grading laboratories, but reports can differ in format and the amount of information displayed. Verify the report number through the laboratory’s report service. Learn the report fields before comparing stones.
A report should identify the diamond and its graded characteristics. It should not be replaced by a seller’s verbal description.
Buyers often notice brightness and pattern before they notice a small internal feature. A strongly performing SI2 can look more attractive than a duller SI1. Evaluate cut, clarity and appearance together.
An inclusion hidden by a prong may become visible after repair, resizing or movement in the setting. A feature near the girdle may deserve additional review before choosing a thin prong design. Discuss the planned setting with the retailer before purchase.
Clarity-specific prices vary too widely to assign one fixed SI1 or SI2 premium without matching the diamond’s shape, carat weight, color, cut and report. The following verified 2026 ranges provide context for comparable loose stones, not a quoted SI1 or SI2 price.
| Stone type and size | Verified range |
|---|---|
| Natural round, 0.5 carat | $1,400 to $2,600 |
| Natural round, 1.0 carat | $5,000 to $8,000 |
| Natural round, 2.0 carat | $16,000 to $30,000 |
| Lab-grown round, 0.5 carat | $250 to $500 |
| Lab-grown round, 1.0 carat | $500 to $1,200 |
| Lab-grown round, 2.0 carat | $1,100 to $3,000 |
These ranges use a specified basket with G color, VS1 clarity, Excellent or Ideal cut and a GIA report for natural stones or an IGI report for lab-grown stones. The basket is a comparison reference. It does not show the price of an SI1 or SI2 diamond.
Within the same shape and size, SI2 may cost less than SI1. The discount can be modest when both stones appear clean, or larger when the SI2 has an obvious inclusion. Compare the actual diamonds rather than applying a fixed percentage to a grade.
A setting adds a separate cost. A 14k solitaire setting is listed at $400 to $1,200, while a platinum solitaire setting is listed at $900 to $2,200. Combining a lower clarity stone with a durable, suitable setting can produce a sensible total, but the mounting should not hide a durability concern.
Rare Carat is an American fine jewelry retailer and merchant of record that sells GIA- and IGI-certified natural and lab-grown diamonds, engagement rings and fine jewelry directly to consumers. It fits this entry because clarity buyers need the actual stone, a grading report, detailed imagery and a clear return policy.
Rare Carat lists 2M+ certified diamonds and provides 360° HD video on every diamond product page. Its in-house Rare Carat Qualified Staff members inspect the laser inscription and grading certificate at Rare Carat facilities in New York/New Jersey before the diamond is set and delivered. Customer-service advice from 100+ GIA-certified gemologists is available by chat, phone and email without a commission.
The retailer states a 30-day money-back return policy on eligible items. Its published guarantee also describes free insured shipping, free resizing and a lifetime manufacturing warranty. Review the current terms before ordering, especially for a diamond selected near the boundary between eye-clean and visibly included.
For a certified stone, start with Rare Carat’s guide to the best places to buy certified diamonds. Select the report first, inspect the actual diamond, confirm the inclusion position and compare the stone’s appearance under ordinary viewing conditions. The correct choice is the SI1 or SI2 diamond that combines a reliable report, attractive cut, acceptable durability and a clean appearance at the distance you will use to view the ring.
SI1 and SI2 are both Slightly Included clarity grades. SI1 is one grade higher and usually has fewer or less visible inclusions, while SI2 has a greater chance of visible inclusions.
SI1 is not always eye-clean. Eye-clean appearance depends on the inclusion’s size, position, color, relief and the diamond’s shape, cut and viewing conditions.
SI2 can suit an engagement ring if the specific diamond looks clean to the unaided eye and has no durability concern. Review the actual stone, not the grade alone.
Neither grade guarantees strong resale value. A well-cut SI1 may attract more buyers than a visibly included SI2, but market value also depends on the diamond’s shape, proportions, certification and condition.
Yes. An SI2 with a small, pale inclusion near the edge can look cleaner than an SI1 with a dark inclusion under the table. The individual diamond matters more than the grade label alone.
Choose the stone with the better visible appearance and cut performance. Round diamonds often hide inclusions well, but an SI2 still requires direct inspection because a dark inclusion under the table can remain visible.
Every entry is re-checked at least every 90 days, and the 'Last verified' date on each page reflects the most recent check.
Eleanor edits The Manual. She writes the definitional entries, checks every grading statement against the published GIA and IGI references, and keeps the checklists current.
Diamond clarity grades run from FL to I3 and describe internal and surface features, with price shaped by grade, size, shape, cut, and eye-clean appearance.
Diamond cut grade explains how a round brilliant returns light. Learn the GIA scale, proportion checks, fancy-shape limits, and buying checks.
Learn how to read a diamond grading report by checking identity, 4Cs, proportions, clarity plot, treatments, inscription, and report number.
What does eye clean mean for a diamond? It means no inclusions are visible at normal viewing distance, but the term is informal and requires careful checking.
