Diamonds - Cross Jewelers
Creating Fine Jewelry for over 100 years in Portland, Maine
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Yes you can shop our store online, our website is open 24 hours a day 365 days a year. You can click and buy, and if you would like to talk with a regular member of our staff, call us:
Monday-Friday 9:30am-5pm EST.
Over 1000 pieces of fine jewelry with mystic appeal, visible and invisible energy. And yes, our showroom is still closed. Order online or give us a call.

Cross' Guide to the World's Most Beautiful Diamonds


Your Diamond Insider

If you love the idea of bright, brilliant, beautiful diamonds selected by a diamond insider, you’ve just made a great discovery.

We specialize in finding the best-of-the-best diamond cutters, not large commercial cutters, but small shops where skills and traditions have been passed from father to son, finely honed and improved from generation to generation. And because they are small shops we can spend time studying each diamond being considered for Cross’ Private Reserve.

We start with an intensive microscopic pre-screening for cut, color, and clarity; choosing only the brightest most brilliant diamonds, choosing only those diamonds that touch the soul… A diamond that speaks the moment it is seen. A diamond that touches the soul is important, for we know that the diamond you give means far more to you than any paper certificate because it will speak for you and to your loved one forever.

Cross Guarantee

We guarantee our diamonds to always be 100%, accurately graded, and to be superbly set into our very finest mountings. We are strict in our grading and highly competitive in our pricing.


A truly colorless diamond is extremely rare. Most diamonds possess varying degrees of yellow or brown and small, subtle differences in color can make a substantial difference in value. Although increasing shades of yellow can reduce the value of a diamond this does not necessarily reduce its beauty. If a diamond is well cut, the diamond’s refraction and dispersion often will disguise certain degrees of coloration.

In addition to specializing in colorless diamonds Cross carries a range of diamond colors.


Cross’ Commitment to Consistency

Of all the factors, cut has the greatest effect on a diamond’s beauty. A Classic Ideal Cut diamond is a fifty-eight facet round diamond adhering to the proportions shown below. It is based on the original calculations done by Marcel Tolkowski in 1919 and published in his book Diamond Design. Tolkowski’s work was revolutionary, resulting in the world standard for ideal diamond cutting. Diamonds are graded and valued on the basis of the four C’s: cut, color, clarity, and carat weight. Ideal Cut always meant one thing and therefore a cut grade of Ideal represented consistency and a guarantee of matchability.

In August 2005 AGS certification and the soon to follow new GIA certification loosened the standards for the definition of Ideal. These new proportions result in some diamonds which formerly would have received cut grades of 1, 2, 3, now being designated on grading certificates as 0 or Ideal. This radical change in the official meaning of the cut grade means two diamonds of identical color, clarity and weight and both having the designation and certification of Ideal could look markedly different in surface appearance, visual performance and diameter size. See below for common deviations from a Cross Ultimate Ideal Diamond.

Consistency is one of the guiding principles upon which our jewelry store is founded. In spite of this loosening of standards, we will continue to adhere to classic Ideal diamond proportions. The ability to match diamonds at the time of sale, as well as in the future, is essential and will always be among our highest priorities. In addition to breathtaking beauty, matchability is why Cross is committed to the Classic Ideal Cut.


The clarity grade of a diamond is determined by the presence, or lack, of internal inclusions and external blemishes under 10-power magnification. Diamonds with very minute internal characteristics are very rare.

Diamonds graded Flawless to SI1 are known as “eye clean” meaning that their internal inclusions are only visible with the aid of a microscope. SI1 diamonds represent excellent values. Cross’ diamond buyer cherry picks the best, always looking at each diamond under the microscope before it becomes part of the Cross Collection.

Carat Size

To see how diamonds compare in size from 1/4 carat to 4 carats print our Diamond Size Comparison Chart. The diamond sizes found on this chart are for strict Ideal-cut diamonds. In recent years the definition of ideal has been broadened to the point that a diamond that weighs one carat can have the diameter and visual look of a .90 carat diamond. In this case you are paying extra for a diamond that looks smaller.

Types of Diamonds Available at Cross


Exceptional ideal-cut diamonds are why so many come from throughout New England and across America to buy their diamond engagement rings from Cross.

THE ROYAL IDEAL – This is the diamond that when she walks into any room anywhere in the world there can be no diamond more brilliant, more beautiful then hers. A Cross Royal Ideal diamond is the ultimate in cutting precision possessing fire, light & life exceeding all others. We specialize in colorless and near colorless Royal Ideals that are triple excellent and are of classic Tolkowsky proportions.

These diamonds are the epitome of consistency and performance. Each 1/3 carat and over is accompanied by either AGS or GIA certification as well as a Cross Appraisal attesting to its quality and value. (ExExEx)

SIBERIAN WHITE IDEAL – Siberian White Ideals possess all of the critical angles and proportions to achieve maximum brilliance and shine. They have tighter proportions then American Ideal and are near colorless and submicroscopic clarity. Siberian Whites are some of our most sought after diamonds. (Ex)

NEW AMERICAN IDEAL – Very nice cutting reflecting the new liberalized GIA & AGS Performance Standards including Hearts & Arrows, and many other name brand diamonds. All color and clarity grades. (Ex)



For all diamonds sold by Cross, we provide final transfer of ownership papers, appropriate certification as well as appraisal documentation to enable you to obtain insurance coverage. Proper documentation represents the pedigree of your diamond and is an important part of your family’s historic record.

Cross Goes Far Beyond the Sarin
We own a state-of-the-art, $25,000, Sarin diamond computer analysis machine. It is capable of a complete analysis and computer printout detailing diamond proportion specifications. The Sarin Computer System can be programmed to determine Ideal proportions and infinitely minute diamond proportion deviations from Ideal allowing the most detailed mathematical qualitative documentation for diamond cutting ever available.

It is important to note the American Gem Society (AGS) classic Ideal cutting standards shown here are the tightest in the jewelry industry. The Sarin can also be programmed to American Gemological (AGL) or (EGL) cutting standard, a bit looser than AGS standards with either numeric or word descriptive cut grades. When a Sarin is programmed to other systems than AGS standards, the grades are typically looser. Therefore any Sarin report and its conclusions of a final grade are not necessarily a guarantee of proper cutting. Specific Sarin proportions and percentages must be compared against the classic Ideal AGS cutting percentages and angles chart. Finally, a Sarin machine does not evaluate polish and symmetry characteristics. This must still be done by the human eye. While a Sarin analysis can pinpoint true Ideal proportions to AGS standards, it is a purely mathematical analysis. As grades deviate from Ideal the Sarin does not accurately assess beauty. Cross’ diamond cut grading system follows Sarin proportions for Ideal Cut grade.

Cross’ system is based on beauty and brilliance, rather than mathematical formulas, therefore Cross Cut Grades for 1-10 are likely to differ from Sarin grades. Sarin currently produces three models of diamond measuring machines. Cross has the top of the line. The same model used by the world’s finest cutting factories and in all American and international gem grading laboratories. The other two Sarin machines produce less accurate reports, especially the retail counter top model. It is important to remember that any Sarin machine can be programmed to appear to draw almost any conclusions. The proof of Ideal proportions is in direct correlation to the American Gem Society classic Ideal standards. Final proof of Ideal Cutting still relies on the human eye.

Impeccable Craftsmanship
Cross is known throughout America for the finest cut diamonds, superbly crafted mountings, but even more important: the final step, diamond setting. We have three master diamond setters on staff who are the best in America. While most diamond setters are on piece work, Cross diamond setters are on salary. The first rule of our diamond setting shop is, “take whatever amount of time is necessary to set the diamond most securely and most beautifully.” This philosophy results in rings that sing with brilliance and beauty, rings that are made for a lifetime of love.


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