Colour Variety


The Hofer Diamond Colour Variety Chart

Natural diamonds occur in fourteen (14) basic colours (i.e., 14 hues), also known as the Colour Variety: Colourless, White, Gray, Black, Violet, Purple, Pink, Red, Orange, Brown, Yellow, Olive, Green and Blue. All diamonds can be organized and classified according to their Colour Variety.

Colour Variety represents Level 2 in the Universal Diamond Colour Language (UDCL).
Each Colour Variety can be expressed in simple terms, by abbreviating in upper case. For example, the six (6) spectral hues – red, orange, yellow, green, blue and violet are abbreviated with one letter R, O, Y, G, B, V, and the other eight (8) hues – colourless, white, gray, black, purple, pink brown and olive are abbreviated with two letters CL, WH, GY, BK, PP, PK, BR, OL.

Diamond Colour Varieties and Abbreviations

 Colourless – CL  Red – R
 White – WH  Orange – O
 Gray – GY  Brown – BR
 Black – BK  Yellow – Y
 Violet – V  Olive – OL
 Purple – PP  Green – G
 Pink – PK  Blue – B

This simple method for abbreviating the 14 colours was developed to facilitate commerce (Hofer 1998). It provides the diamond market with a Universal code for abbreviating colours, and it easily communicates a specific Colour Variety (e.g., CL) to a global audience. Every single diamond (regardless of whether it is a rough crystal or a polished gemstone) can be classified (organized) according to the specific Colour Variety it belongs, and abbreviated with a simple (alphabetic) code.

The more familiar someone is recognizing and perceiving – the 14 basic colours (hues) in the world around us – the easier it will be for them to recognize and perceive which Colour Variety a particular diamond belongs/exhibits.

Therefore people interested in this subject (i.e., buyers, sellers, appraisers, cutters, dealers, jewelers, auctioneers, collectors, investors, consumers) must become very familiar with these basic 14 colours. Why? Because the financial success (i.e., profit/loss) incurred when buying/selling any natural diamond, depends on what specific Colour Variety diamond you are dealing with. For example, some colours are naturally rarer than other colours, and some colours are perceived as more beautiful than other colours – thus it is vital to know the exact Colour Variety of any diamond before you begin a dialogue about value and price.

Describing the Colour Variety (main hue) of any diamond is merely the next step (Level 2) in the UDCL (Universal Diamond Colour Language), (Hofer 1998). People unfamiliar with the UDCL method of colour description quickly realize the UDCL is fun and easy to use, because it offers everyone the opportunity to use their own eyes to perceive the 14 basic colours.

As we learn more about perceiving colour in diamonds, we begin to realize that looking at diamonds presents a unique (visual and mental) challenge – i.e., there is an “art” to looking at colour in a diamond. For instance, with Colour Variety we are merely trying to use our own eyes to see, and our minds and colour memory to decide – which of the 14 Colour Varieties is the appropriate choice for describing a particular diamond.

Eventually, everyone involved with natural coloured diamonds must learn to commit all 14 colours to rote (colour) memory. Why is this so important? Because every single diamond colour description – begins with knowing the exact Colour Variety. Since there are only 14 choices to select from, people consider this a fun exercise for the eyes and a stimulating challenge for the mind – to get visually and mentally “acquainted” with each colour variety.

Using our eyes, brain and colour memory to visually (i.e., subjectively) decide – whether a (rough/polished) diamond is a member of a certain Colour Variety – seems simple enough. For example, we know through the use of instrumental (i.e., objective) colour measurement, that nature has created diamonds in 14 visually distinct Colour Varieties (hues). Objective colour measurement also confirms, that each Colour Variety (hue) is different from the other hues (i.e., visually different and numerically different).

In fact that is the fun part for a diamond colour researcher like me. For example, I enjoy looking at all the diamond colours with a critical eye (i.e., hue, lightness and saturation), and I enjoy measuring these colours with a suitable instrument (i.e., gemstone colorimeter), which results in a set of three (3) numbers to define each colour. With this numerical colour data (CIELAB) in hand, I enjoy organizing (classifying) all the different diamond colours we might encounter (i.e., natural colours and man-made colours), and arranging them in their exact position within 3-D colour space. Once I know where a particular colour plots within 3-D colour space, I can use the numerical colour data (Level 6) to further describe any particular colour verbally – according to the UDCL: main hue (Level 2), minor hues (Level 3), lightness (Level 4) and saturation (Level 5).

In other words, studying natural diamonds and measuring their colours is a lot of fun, because it’s like working on an intricate colour puzzle with thousands of different colours. The diamond colour puzzle is unique, because there are literally thousands of subtle colour differences (i.e., hue, lightness, saturation differences) evident in diamonds. After nearly 40 years of diamond colour research, I have ample scientific evidence (CIE colorimetric data) that confirms a NEW paradigm for the diamond – i.e., natural diamond is the “ultimate coloured gemstone” (based on the incredible diversity of colours found in nature)!

For anyone interested in this subject or new to this subject (consumer/novice), all you have to do to appreciate the extensive diamond colour palette, is simply “look” at each diamond (i.e., under a prescribed set of lighting and viewing conditions), and then “decide” with your own mind and memory, which Colour Variety a particular diamond belongs. This next step (UDCL Level 2), is how anyone can develop their own colour acuity, develop their colour awareness and colour perception, and improve their colour dialogue, i.e., one colour at a time. Simply begin by trying to figure out for yourself, which one (1) of the 14 Colour Varieties a particular diamond belongs?

Admittedly, one could also rely on the opinions of others (i.e., laboratory grading reports), to establish the Colour Variety (i.e., according to the various guidelines issued by each diamond grading laboratory). Or one might consider doing both, i.e., using your own eyes and colour memory to define and describe the Colour Variety of a particular diamond, and then refer to an existing diamond grading report, to compare the lab’s opinion of the Colour Variety, with your own opinion.

As I mentioned, it is truly a fun and challenging experience to look at any polished diamond, and assign a specific Colour Variety to that particular diamond. In some cases – i.e., where the main colour is obvious, it is easy to say that a particular diamond is a member of the yellow (Y), or brown (BR), or colourless (CL) variety. However, in other cases – i.e., where the main colour is not obvious, it is not so easy to decide by eye what the main colour (variety) of a diamond is.

This occurs because nature has done something quite special with diamond… i.e., nature has given diamonds way more colours than most people would ever expect, or would even consider possible. The actual number of different colours (i.e., hues, lightness, saturation) that natural diamonds exhibit – is truly remarkable (5,000+).

This is why it is so important to start any dialogue about diamond colour description at the beginning… i.e., by assigning a Common Colour Name (UDCL Level 1), and then assigning the appropriate Colour Variety (UDCL Level 2). Once you have established the Common Colour Name (e.g., lemon) and the Colour Variety (e.g., yellow) of a diamond, you are one step closer to accurately and precisely describing the exact (i.e., true) colour of that particular diamond.

This human ability to perceive colour – i.e., to recognize the 14 visually distinct colour varieties and remember each of them correctly in our colour memory, and to look at any unknown rough/polished diamond and decide which Colour Variety it belongs – is an acquired skill. Fortunately this visual skill can be learned by anyone, regardless of prior experience – it just takes a little effort and determination to perceive, remember, and organize exactly what (colour) you see.

It also requires a simple method to organize ALL the different colours nature has created in diamonds (UDCL Levels 1-6), so that everyone is speaking about colour on the same level (i.e., using an accurate and consistent colour dialogue for describing colour in diamonds).

For example in this next group of photos, the diamonds are described according to the particular Colour Variety they belong (UDCL 2). Whereas in previous photos, the diamonds were all described according to the most appropriate Common Colour Name (UDCL 1).

By showing diamonds from each of the 14 Colour Varieties (e.g., a selection of diamonds from the purple Colour Variety), this will eventually get more people acquainted (visually and mentally) with how each of the 14 colours actually appears in diamond. These Colour Variety photographs will also help more people to understand and appreciate the extreme range of colours that nature has given each diamond Colour Variety (i.e., by showing a few unusual examples, that people may not associate with a particular Colour Variety).

For example, the range of brown (BR), orange (O), pink (PK), yellow (Y), olive (OL) and green (G) variety diamonds is quite extensive in nature. In other words, these Colour Varieties exhibit a wide variation in the number of secondary hues (i.e., Colour Modifiers), and they exhibit a wide variation in Lightness (i.e., light/dark), and a wide variation in Saturation (i.e., weak/strong).

Whereas, the range of violet (V), purple (PP), colourless (CL), white (WH), gray (GY), black (BK), blue (B) and red (R) variety diamonds is limited. For example, diamonds in these Colour Varieties might exhibit fewer Colour Modifiers, and/or they exhibit a smaller range of Lightness, and/or a smaller range of Saturation, than the other colours.

For example, natural brown (BR) variety diamonds are known to exhibit an extraordinary number of secondary Colour Modifiers (UDCL-3). Brown diamonds also occur in several different Lightness levels (UDCL-4), and they exhibit several different Saturation levels (UDCL-5). This makes for quite a diverse range of colours all classified within the brown (BR) Colour Variety.

Whereas natural violet (V) variety diamonds only exhibit a few Colour Modifiers, and they occur in a limited range of Lightness and Saturation (i.e., colour tone). This means that natural violet diamonds exhibit a modest (limited) range of colour differences within the violet (V) Colour Variety, as compared with other colours.

The point is… the more you look at diamonds with an eye for dissecting and organizing colour(s) according to the UDCL (i.e., Levels 1-6), the easier it will be for anyone (i.e., novice or professional) to assign the correct (i.e., true) colour description to any unknown diamond – and eventually determine its true Value ($-$$$) in the marketplace.

Keep in mind that Colour Variety merely represents Level 2 of the six-level Universal Diamond Colour Language (i.e., a simple way to verbally describe the main hue of any diamond). Once you understand the concept of Colour Variety (Level 2), and you can recognize each of the 14 Colour Varieties with your eyes (i.e., colour perception), and you can remember these 14 basic colours in your mind (i.e., colour memory) – then you are ready to move up to the next level of colour description (UDCL Level 3), Colour Modifiers.