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The 4Cs


At Lucano, we believe that while every diamond should be chosen with the heart, it must be verified with precision.

We strictly adhere to the GIA grading system—the gold standard of the international diamond trade.

This ensures that the stone you choose is evaluated with total transparency, removing any bias and focusing purely on the physical characteristics that define its value.

Diamonds Education

GIA D-to-Z Color Scale

Color is inherently relative, and before a universal standard existed, describing it was a challenge.

Historically, the jewellery trade used a confusing mix of Roman numerals, letters, and vague descriptors like 'blue-white.' This lack of consistency often led to misunderstandings and inaccurate representations of a diamond's true quality.

In 1953, the GIA transformed the industry by introducing the D-to-Z Color Scale. By choosing to start with the letter 'D', distancing the new system from the 'A, B, C' grades used in lesser scales, they established a definitive system of absolutes. This ensured that diamond grading would finally be objective, precise, and globally recognized.

Today, the GIA scale measures the 'depth' of a diamond's color within the normal range from D (completely colorless) to Z (a light yellow, brown, or gray tint). At Lucano, we rely on this internationally recognised benchmark because it accounts for the microscopic variations in hue that define a diamond's quality. It is this standard of precision that allows us to provide you with total transparency and confidence in every stone we select. Click here for more

What does Fancy color mean?

While the D-to-Z scale covers the 'normal' range of diamonds, nature occasionally produces something truly extraordinary. Any diamond that falls outside this traditional spectrum is known as a Fancy Color Diamond.

Because these stones are so rare, the industry uses the term 'Fancy' to describe diamonds that exhibit a color depth more intense than a 'Z' masterstone, or those that display entirely different hues altogether such as vibrant pinks, blues, greens, or oranges.

While 'Fancy' doesn't have a single universal guideline, it is widely accepted as the benchmark for diamonds with a distinct, saturated character. Whether it is a deep canary yellow or a rare champagne brown, these stones are prized for their individuality. At Lucano, we specialise in sourcing these rare treasures, helping you understand the unique factors that make Fancy Color diamonds a category of their own.

Technical Mastery of Diamond’s Cut

At Lucano, we view the cut of a diamond as the ultimate fusion of art and technology.

While nature provides the raw material, it is the precision of the craftsman that unlocks a diamond’s brilliance. Our grading standards are constantly evolving, incorporating the latest state-of-the-art technologies and observational studies to ensure that the results we provide are the most accurate and trustworthy in the industry.

When evaluating a diamond's interaction with light, we analyze several critical factors:

  • Brightness: The total volume of white light reflected from both the internal and external surfaces of the stone.
  • Fire: The spectacular scattering of light into a vibrant rainbow of spectral colors.
  • Scintillation: The mesmerizing interplay of light and dark areas the 'sparkle that occurs when the diamond moves.
  • Weight Ratio: A comparison of the diamond’s total weight against its face-up diameter, ensuring the stone isn't 'bottom-heavy.'
  • Durability: An assessment of the diamond’s proportions to ensure it is structured to resist damage or chipping.
  • Polish: The smoothness and overall condition of the finished facet surfaces.
  • Symmetry: The exacting precision in the placement and alignment of every facet.

More About cut

When you hear words like Brightness, Scintillation and Fire, they describe how masterfully a diamond is cut.  

A diamond’s cut refers to how it interacts with light.

While a term like oval would refer to the shape, or outline of a diamond, cut also describes the overall design of a diamond, including the arrangement and proportions of the diamond’s facets. 

Assessing the major components of a diamond, as well as its ability to interact with light, the Diamond Cut Grading System provides a standard system for consistently evaluating and documenting the cut quality of a standard round brilliant diamond from Excellent to Poor. This allows both gem and jewelry professionals and customers to make informed decisions when purchasing or selling a standard round brilliant diamond.  

The major components of a standard round brilliant, from top to bottom, are crown, girdle and pavilion. Every round brilliant cut diamond has 57 or 58 facets, the 58th being a tiny flat facet at the bottom of the pavilion that’s known as the culet. The large, flat facet on the top is the table. 

Standard round brilliant cut diamonds in the D-to-Z color range are assessed by their face-up appearance, design and craftsmanship.

Diamond cut grades are only given to round brilliant cut diamonds because they are the only cut that have standardized facets. 

All other shapes are referred to as fancy shapes, which includes marquise, emerald, pear, oval, hearts and even triangles.  

Proportions impact the face-up appearance, allure and attractiveness of diamonds. There are many components to consider when assessing the overall cut quality of a round brilliant diamond, one of which is the individual’s preference. Each grade range represents a range of proportion sets, so there is plenty of room for personal preference within a preferred grade range. 

There is a nearly unlimited combination of proportions possible, and all of them impact the interaction with light, and ultimately how attractive the diamond appears. 

Diamond Clarity: Nature's Fingerprints

Every diamond carries a unique history.

Formed under staggering heat and pressure deep within the earth’s mantle, it is natural for diamonds to contain what we call 'birthmarks.

These characteristics are formed when microscopic crystals become trapped within the diamond as it grows. The resulting stress can create internal features (inclusions) or surface-level traits (blemishes) that are often invisible without professional equipment.

At Lucano, we evaluate a diamond’s clarity based on a combination of five factors: the size, nature, number, location, and visibility of these traits.

  • Inclusions: Internal characteristics that are entirely enclosed or reach the surface from within.
  • Blemishes: External features confined to the surface of the stone.

Because many of these details are hidden from the naked eye, achieving gemological accuracy requires specialised expertise. In line with the GIA’s global standards, our assessments of clarity, polish, and symmetry are only finalised under a 10x magnification loupe or a high-powered microscope. This level of precision is the secret to an accurate valuation and is essential in ensuring you secure a diamond of true quality.

Diamond Clarity Grading System

1 Universal System. 11 Grades.
All under 10x magnification

Flawless (FL) – No inclusions and no blemishes visible.

Internally Flawless (IF) – No inclusions visible but does have blemishes.

Very, Very Slightly Included (VVS1 and VVS2) – Inclusions so slight they are difficult for a skilled grader.

Very Slightly Included (VS1 and VS2) – Inclusions are observed with effort but can be characterized as minor.

Slightly Included (SI1 and SI2) – Inclusions are noticeable.

Included (I1, I2, and I3) – Inclusions are obvious which may affect transparency, brilliance and durability.

Diamond Carat Weight

A common misconception is that carat refers to the physical size of a diamond. In reality, Carat is a precise unit of weight. One metric carat is exactly 200 milligrams.

To ensure total accuracy, each carat is divided into 100 'points.

For instance, a 0.50-carat stone is often called a '50-pointer,' while stones over one carat are described by their decimal, such as a 'one-point-zero-eight' (1.08) carat diamond.

The term itself is a nod to history. Since the 1500s, gem traders used carob seeds as uniform counterweights for their scales. While we now use highly calibrated electronic sensors, the name remains as the global standard for gemstone measurement.

Why Weight Doesn't Always Mean Beauty

While a higher carat weight typically indicates a rarer and more expensive diamond, 'bigger' isn't always better. At Lucano, we prioritise the harmony of all 4Cs. Two diamonds of identical weight can look vastly different if one is cut poorly; a well-cut 0.90ct diamond can often appear more brilliant and even 'larger' to the eye than a poorly cut 1.00ct stone.

The Secret of 'Magic Sizes'

In the world of diamonds, certain weights like 1.00ct, 1.50ct, and 2.00ct are known as 'Magic Sizes'.

These milestones are highly sought after, which causes their price to jump significantly. Interestingly, the visual difference between a 0.99ct diamond and a 1.00ct stone is virtually impossible to detect with the naked eye, yet the 1.00ct stone will carry a premium price tag.

Understanding these nuances allows us to help you find a diamond that offers the greatest visual impact for your investment.