Before you get into studying shades on stamps it is useful to understand the subject of colour as it relates to philately in general. The issue of colour is perceived by philatelists to be highly subjective and individualistic, not to mention confusing. One of the biggest problems in the hobby is that terminology is used very loosely, with very specific words being used as though they are synonyms, when in reality they mean very different things. For example, a dark colour and a deep colour are not the same thing at all, even though they sound the same. Yet many collectors will use these terms interchangeably. In addition, most listings in the standard postage stamp catalogues use words that are far too general to describe colour, such as "green", or they use culturally loaded terms like "Indian red" and "Pigeon Blood Pink", which are just about useless for identification unless you know what the exact colour looks like.
The result of all this confusion is either a large number of completely mis-identified stamps, or no attempt made at all to correctly identify shades, with dealers and collectors alike opting to just assume that they have the "cheapest shade". My hope in writing this article is to show you that with a proper understanding of the language of colour and the proper use of a standard colour key, such as the Stanley Gibbons colour key, you will be able to confidently identify colour with much more objectivity than you may have thought possible.
Correct Use of Colour Terms: Hue, Saturation and Value
A hue is simply a name given to a pure colour such as "red", or a combination of pure colours such as orange-red. This is the first area in which collectors use terms interchangeably when they mean different things. Most often collectors will refer to the "shades" of colour on a stamp issue. However the term "shade" is actually a specific term that refers to the value of a colour, as I will explain below. Some of the colours found on a stamp issue will be shades in the truest sense of the word, but some, as we shall see are pure hues as well.
The second area of confusion when it comes to hue is the interpretation of compound colour names such as red-orange and orange-red. Many people will use these names interchangeably, when they refer to completely different hues. The correct way to interpret these names is to understand that the second colour in the name is always the predominant colour, while the first colour is the modifying colour. So:
- Orange-red is red with a tinge of orange, while
- Red-orange is orange with a tinge of red.
Saturation refers to how pure a hue of colour is. It is a measure of a colour's intensity. The concept of saturation includes the following commonly used terms:
At one end of the scale are the pure chroma hues that are fully saturated. For colours that are naturally fully illuminated and vivid, we call those "bright". Colours that are not illuminated, but are pure in terms of intensity are usually termed either "intense" or "deep". A colour can be either of these two extremes:
- Deep blue and intense blue are pure blue with no illumination.
- Bright blue is a pure blue that is fully illuminated
It is important to note that the illumination does not come from the addition of white to the colour: it is a pure hue with nothing added.
At the other end of the scale are those colours that are de-saturated and appear duller or washed out. Such colours are called "dull", or "pale". Again, the dullness can come either from a lack of saturation, or from the addition of grey to the colour. However, the proper term for a colour which has had grey added is a "tone" of the colour.
- Pale blue is the opposite of deep blue on the scale, whereas:
- Dull blue is the opposite of bright blue on the same scale.
Soft colours are usually either pale or dull.
Value refers to lightness of colour or darkness. Both of these terms refer to the addition of either white or black to a colour. A shade is obtained when black is added to a colour, whereas a tint is obtained when white is added. A tone is obtained when grey is added to a colour. So to continue the example above, with blue:
- Dark blue is pure blue that contains at least some black. It is thus not the same as deep blue, which contains no hint of black.
- Light blue is pure blue that contains at least some white. It is thus not the same as pale blue, which contains no white at all.
- Dull blue can be a blue that has been desaturated by adding grey. it is a tone of blue.
Warm Versus Cold Colours
Another set of terms that we often see in the philatelic literature, particularly in the Stanley Gibbons catalogues are warm versus cold shades.
Warm colours are those that contain a yellow, red or orange undertone. An example of a warm red colour is scarlet. Scarlet contains a hint of orange usually.
Cool colours in contrast are those that contain a blue undertone, or which simply lack the yellowish undertone of warm colours. An example of a cold red is Carmine. Carmine is a red that always has a bluish undertone.
So occasionally, you will see a reference to a colour being warmer, or cooler. When you see that think about whether it has more of a yellowish undertone versus a bluish one.
The Stanley Gibbons Colour Key and Learning to Use it Properly