Watercolour is one of the quintessential techniques in the world of art, yet it contains a lot of information unknown to the vast majority of people who paint in this medium.
Commercial brands give their products names that sometimes don't tell us everything about what they contain, which is why more detailed information needs to be included on the label.
It is important to know what they mean and how to read the symbols on the labels of water colours, which you will find not only on the tubes, but also on the packaging or on godets.
It is important to know what they mean and how to read the symbols on the labels of water colours, which you will find not only on the tubes, but also on the packaging or on godets.
In this article, we will help you to understand the most common symbols used and what characteristics they refer to:
- ASTM or lightfastness rating:
The American Society for Testing and Materials is the association that establishes all the standards for art materials, unifying the criteria for determining the characteristics of these.
The letter rating system is as follows:
AA – Extremely Permanent
A – Permanent
B – Moderately Durable
C – FugitiveSome companies use different icons for lightfastness:
Royal Talens uses a system of noughts and crosses (o, +, ++, +++) running in opposite directions so that o is the least lightfast and +++ the most.
Schmike uses a star system that works the same way, ★ being the least lightfast and five stars being the strongest.
Other use asterisks with a maximum of seven ones (*******) for extremely lightfast hues.Finally, another rating system is by using Roman Numerals, where I is the highest, II and III medium, IV low and V and VI the lowest.
This will indicate the alterations that colours exposed to light may undergo over time. - Opacity or transparency:
Represented by a square that may appear filled with black, indicating maximum opacity, half black, half transparent or white (medium-high), cut diagonally transparent or white (medium-low) and only with the outer lines, which would be the lowest degree.
Colour layers will have more hiding power at higher opacity. - AP Seal (ACMI):
An approved product of the Arts and Creative Materials Institute, Inc. This association is made up of more than 200 manufacturers who seek to promote safety in art.
The seal identifies that the pigment has been evaluated as a safe material and does not contain materials that are harmful to humans or the environment.
- Series:
The series to which each colour belongs within each brand's range. The highest series are those containing pigments that are more difficult to obtain and therefore have a higher price. - Pigment number:
The pigments are identified by an alphanumeric code, which serves as a guide to know that it is a quality pigment. Even if the pigment number used is the same, the colour does not have to be exactly the same. - -PW (white)
- -PY (yellow)
- -PO (orange)
- -PR (red)
- -PV (violet)
- -PB (blue)
- -PG (green)
- -PBr (brown)
- -PBk (black)
- Granulation:
Some pigments give a grainy appearance when applied diluted on paper. A G may appear to indicate this; Yes or No in other cases. This may vary from brand to brand
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Keeping each of these categories in mind when buying our watercolours will help us to get better and more direct results.
So, what should I base my choice of watercolours on?
It will always be a matter of taste and will depend on several factors, such as the medium we are going to use, what we want to achieve or who it is aimed at.
We advise you to choose a product based on a single pigment, as the more mixture they contain, the dirtier and duller they will make your work. On the other hand, pure pigments will make your paper look cleaner.
