In addition to jewelry, Valentin Magro offers loose diamonds for sale. They come in a variety of cuts shapes and sizes, from the classic round brilliant to modern cuts such as the princess. All of our diamonds are certified by the Gemological institute of America. Many of these loose diamonds are featured on our website for your perusal.

Purchasing loose diamonds allows for flexibility. If one has trouble finding the diamond jewelry they desire, they can start with loose stones. Sometimes finding the right jewelry begins with finding an attractive gem. The jewelry can then be planned around the jewel. Valentin Magro specializes in custom jewelry. From casual pieces to extravagant creations, we strive to make your ideas a reality. Every creation that passes through our hands receives the utmost care and consideration.

The loose diamonds you ask us to design jewelry for is no exception. To better help you choose which loose diamonds you desire, the jewels we feature on our website come with detailed information. Each diamond is represented with a photograph and caption naming its cut and carat. By waving a mouse over the image, a button labeled “view details” appears. Clicking on this reveals a list of details from the gemstone’s 4cs to its certificate type, number and even its symmetry.

Engagement rings with Certified diamonds

Certified Loose Diamonds from Valentin MagroEngagement rings, wedding bands and anniversary bands are commonly mounted with diamonds. This custom started in 1477 with the diamond engagement ring Archduke Maximillian of Austria gave to his fiancé Mary of Burgundy. Over time, as diamonds became more available and affordable, more people wore diamond bands commemorating their engagement, marriage and time together.

Certified diamonds aim to provide documentation of a diamond’s quality, assuring connoisseurs as to the type of stone they’re purchasing. Independent third party laboratories such as the Gemological Institute of America strive for impartial grading in the hopes of getting the most accurate information possible. Jewelers such as Valentin Magro prefer GIA certified diamonds due to the institute’s longstanding reputation for excellence and innovation.

Modern engagement rings and other meaningful diamond bands are mounted with certified diamonds. When buying diamonds that represent a life together, many want to make sure what they’re getting meets their standards. This is where certified diamonds come in. We want to make sure that your rings are everything you desire. Our GIA certified diamonds will give your rings security along with beauty. Each jewel comes with a unique GIA ID number, allowing you to reference its qualities whenever you wish.

A Closer Look at Clarity Characteristics

All diamonds at Valentin Magro are GIA certified diamonds. Each GIA Diamond Report comes with a diagram plotting quirks in the jewel’s crystal, also known as clarity characteristics. While there are grades denoting how clear or included a diamond is, no two jewels have their clarity expressed the same way, making characteristics a form of identification. Diagrams help illustrate these differences.

All diagrams begin with a drawing of a diamond as seen from the top and bottom. These images are much larger than most jewels, allowing for ease in plotting clarity characteristics and for viewing details of the completed pictures. Different colors are used to mark various types of quirks in certified diamonds, such as black for extra facets and red for inclusions. There are many different types of clarity characteristics that may occur in certified diamonds. Blemishes sit on the surface of a gem and include things like polish lines or chips. Inclusions happen within the jewel, and may be anything from a minute pinpoint to thin needle crystals or internal graining. Some inclusions may even reach the surface.

Every characteristic is marked with a different symbol, with a legend explaining what each symbol means.  Diamonds are examined for characteristics at 10x magnification. When a quirk is found and identified, it’s noted on the diagram on the place it’s found on the jewel. People with GIA certified diamonds can use these diagrams as reference points to help identify their stones, while prospective buyers may use them to help inform their purchase.

GIA Reports

One of the reasons Valentin Magro uses GIA certified diamonds is that the Gemological Institute of America is constantly improving how it grades diamonds. Early innovations include patenting jeweler’s loupes and creating the 4Cs grading standards of cut, color, clarity and carat. A more recent development occurred in 2014, altering the format of Diamond Reports.

Among the goals for the updated report was to make them easier to read, so owners could better understand the quality of their certified diamonds. The newer version has a unique report number at the top center of the report to facilitate looking it up on the GIA website. Grading scales for color, cut and clarity are on the right side of the certificate, allowing readers to gauge where the stone fall within the 4Cs. On the left side are the diamonds 4C grades, as well as shape, measurements and other identifying traits. The center features diagrams marking the diamond’s proportions and distinctive clarity characteristics.

The updated report uses less materials in order to be more environmentally friendly. The paper it’s printed on is also designed to be unique to GIA certified diamonds. This adds another identity marker to the reports, making it more difficult to confuse GIA documents with those of another organization.


On the right hand side of GIA certified diamonds’ reports are a list of the 4Cs grades, dimensions and other features. One of the traits mentioned is whether or not a diamond had fluorescence, and if so, how strong. As with factors like clarity, total depth or girdle inscriptions, fluorescence is used to help distinguish diamonds from one another. When some diamonds are exposed to long wave ultraviolet light, they glow. Among the types of light with long wave UV rays are everyday sources like sunlight and fluorescent lamps. This shine lasts as long as the diamond remains under the ultraviolet light. Only twenty-five to thirty-five percent of certified diamonds have fluorescence.

As with color grading, GIA certified diamonds are compared against master stones to determine the degree of fluorescence. Diamonds are rated on a scale from None, Faint, Medium Strong, and Very Strong. If a stone is Medium or higher, its color is noted on the report. Most diamonds with fluorescence glow blue, though other hues such as yellow or orange may appear.  Fluorescence may have a subtle effect on a diamond’s apparent color, making the jewel appear whiter or bluish. This is difficult to detect with an untrained eye, and has no effect on a stone’s color grading. GIA certified diamonds are evaluated under controlled lighting to ensure color is judged as accurately as possible.

Nature and the Lab

Diamond’s unique physical properties make it ideal for industrial purposes from drills to semiconductors. To help meet demand, diamonds are created in laboratories, where formation is controlled. Most of these stones go on to be used in tools, though some may be of gem quality. One of the first tests all GIA certified diamonds undergo is to determine if they are natural or synthetic.

Only natural diamonds may receive Diamond Reports or Diamond Dossiers. Laboratory made jewels are graded by different standards and receive certificates which explicitly label them as synthetic. Among the ways GIA certified diamonds are screened for their origins is by examining the nature of their clarity characteristics. Natural diamonds contain inclusions which bear traces of their time in the earth, such as internal crystals. Other screening processes include scanning jewels for traces of nitrogen. Ninety-eight percent of natural diamonds have trace nitrogen. Gemstones without it are subject to closer examination.

A Closer Look at Cut

Diamonds in their rough state have luster, but no brilliance. Light reflects off of its surface while internal shine is scarce. Paintings that feature early diamond cuts show black jewels. To achieve ideal brilliance, diamonds must be cut to careful proportions and symmetry. GIA certified diamonds gauge how well a gemstone is shaped.

GIA’s cut grades are Excellent, Very Good, Good, Fair, and Poor. Certified diamonds with an Excellent rating should have an even distribution of light within the jewel, with balanced patterns of brightness and dark. Diamonds graded as Good may have patches of shadow that are disproportionate to its brilliance. Poor jewels may have exaggerated proportions which impact their appearance. Factors that go into determining cut quality include symmetry, proportion, girdle thickness and polish. Certified diamonds are studied using a combination of advanced machinery and examination by eye to evaluate their cut. As there are multiple ways for a jewel to be beautifully cut, this step can be complex.

Certified Loose Diamonds from Valentin MagroSymmetry allows for even light distribution within the jewel, allowing for greater brilliance or to showcase the interior of the stone. Proportional certified diamonds have a total depth and facet angles that allow for optimal reflection within the gem. Neither the upper or lower halves of the diamond should be too steep or shallow. The thickness of the girdle, or the outermost perimeter of the diamond, shouldn’t be too deep or thin. Knife edge girdles are prone to chipping, while overly wide ones may darken the stone.

The type of cut also matters. Brilliant cuts have a heavy emphasis on sparkle, while step cuts promote the clarity and luster, or surface shine, of a jewel. Mixed cuts combine the qualities of brilliants and steps, while fancy cut certified diamonds have unusual shapes such as hearts or pears. Each type has different factors which make them attractive. When selecting certified diamonds, remember that you are the best person to decide what cut you prefer. Diamond grades indicate which jewel is skillfully cut, but you make the final choice. This includes determining if you prefer a mixed cut over a brilliant, or if you prefer the look of a specific Very Good cut diamond over one with an Excellent grade.

Diamonds and Light

Diamonds are prized for their extreme hardness, which has been used for centuries to represent the bonds of love. However, to bring out the full appeal of a diamond there needs to be light. Not only is light crucial to display the color of a jewel, it also showcases diamond cuts to their best ability. How light performs is also essential for evaluating GIA certified diamonds.  In 1919, PhD student Marcel Tolkowsky published a paper titled “Diamond Design.” How light and diamonds intersect was the backbone of his publication. This work outlined the number of facets, table size, pavilion angle, and other details of how to cut a diamond for optimal reflection. Certified diamonds today are graded based on standards he created.

GIA certified diamonds receive cut grades based in part with how they interact with light. Ideal brilliant cut diamonds should be a mix of light and shadow, with one balancing the other. The types of light evaluated are brilliance, fire and scintillation. Brilliance refers to the white light reflected within and from the diamond, fire is the term for flashes of colored light, and scintillation is the play of light and dark. All of these combines to make eye catching diamonds.

Some fancy cut certified diamonds, such as the marquise or oval, have shapes that lend themselves to shadows in the center of their stones. These patches of darkness resemble two connected triangles, referred to as a bowtie. Diamond cutters aim to make this shadow as small as possible so as not to detract from brilliance. A diamond’s color too is influenced by light. White light is a combination of all the colors in the visible spectrum.

Depending on the diamond’s crystal structure or the presence of trace minerals, some hues may be absorbed while others are reflected, which appears to the viewer as a tint. With most stones this appears as a subtle hint of yellow or brown. Color grading certified diamonds determines the strength of this tinge.  GIA certified diamonds are graded under conditions with specialized lighting. It’s controlled to reduce as many variables as possible for color grading, such as accidentally making a stone seem more yellow than it is. Diamonds are evaluated for color in boxes that provide ideal lighting against neutral backgrounds to further aid in accurate grading.

Cut and Carat

While there are gem quality diamonds such as the Excelsior or Golden Jubilee which have massive carat size, most rough are of modest size. The geological activity which forms diamonds is more conducive to creating smaller stones, adding to the rarity and value of larger diamonds. At the same time, most cut diamonds, especially brilliant cuts, must sacrifice larger amount of rough to garner a high grade. When diamond cutters shape jewel, they try to find a balance between the two demands.

Diamond cut and caratRound brilliant cut diamonds have been beloved for nearly a century due to their ability to take in and reflect light. To promote symmetry and bring out its best light, about half of its rough must be sacrificed. Some cutters aim to preserve weight by leaving extra facets or creating a thicker girdle, though this may impact cut or clarity. Diamond cuts whose outlines follow the shape of the original octahedral rough are better able to preserve carat.

Cushion cut diamonds were developed as an early method to preserve carat weight while promoting brilliance. The shape could be anywhere between a square or a circle, and the number of facets varies. Modern cushion cuts are brighter than their ancestors, but still don’t have a standard design. Newer developments in cut and carat include mixed cuts like the radiant and the princess. They often have lower halves cut for brilliance while their upper halves have fewer, broader facets.

The desirability of larger cut diamonds is linked to magic sizes, diamond’s value increases drastically at 0.25 carats, 0.5, 0.75, a full carat and so on. For buyers, this means the ability to purchase a 0.99 carat jewel that appears similar to a one carat jewel, but with a notable price difference. GIA certified diamonds are weighed under strict circumstances, allowing for accurate measurements and determining if a jewel exceeds a magic size.