At Rosenberg Diamonds & Co., we believe that true luxury begins with trust, precision, and authenticity. When it comes to evaluating the quality of a diamond, there is only one global authority we rely on, the Gemological Institute of America (GIA). GIA is the founder of the universally recognized 4Cs—Carat, Cut, Color, and Clarity—and has set the gold standard for diamond grading worldwide.
Every diamond in our collection is exclusively graded by GIA, ensuring complete transparency and unwavering accuracy. Unlike other laboratories that may use more lenient or inconsistent standards, GIA is known for its strict grading practices and impartiality.
Carat refers to the weight of a diamond, not its size, though the two are often perceived together. One carat equals 200 milligrams, and diamonds are measured to the hundredth decimal, showcasing their precision. While carat weight plays a significant role in a diamond’s presence and value, it is not the sole determinant of beauty. A well-cut smaller diamond can outshine a larger one if it captures and reflects light more brilliantly.


The cut is often considered the soul of a diamond. It determines how the stone interacts with light, its brilliance, fire, and scintillation. Far beyond the shape, cut quality refers to the proportions, symmetry, and polish that bring a diamond to life. A masterfully cut diamond transforms a rough diamond into a living spark, maximizing its natural radiance.



Diamonds come in every color one can imagine. From the colorless Golconda Type IIa ‘whiter-than-white’ stones of legend to a kaleidoscope of fiery shades across the spectrum, the diamond remains one of Earth’s most beautiful and versatile natural treasures.
A diamond’s color quality is typically determined according to standards set by GIA. White diamonds are graded under controlled lighting and compared to ‘master stones’ on a scale ranging from D (complete colorlessness) through Z (yellow or brown hue).
The 4Cs are the universal language of diamond quality. At Rosenberg Diamonds & Co., they are the starting point, not the finish line. Every stone in our collection meets the absolute pinnacle of all four criteria. But what truly defines a Rosenberg diamond goes further: it is the rarity of its origin, the significance of its color or purity, and the certainty of its GIA certification. These are stones acquired by collectors who understand that the most important diamonds cannot be fully described by a grading scale, only experienced in person. Private consultations by appointment in Boca Raton, South Florida.
Thank You!
Your request has been sent. We will get back to you shortly.
To provide the best experiences, we use technologies like cookies to store and/or access device information.