Making soft pastels

If you can make mud pies, you can make soft pastels. This page summarises my experiments in the craft. I hope you find it interesting and useful, and want to try to make your own.

My starting points were The Artist's Handbook by Pip Seymour (Arcturus, London, 2003, pp520) and a catalogue on Cornelissen's website: (http://www.cornelissen.com/pdf/pastels.pdf).

If you do have a go at making pastels yourself, I recommend you follow the safety instructions published there: all the materials are dusty, and some metallic pigments (such as the cadmiums and chromes) could be hazardous if you don't take sensible precautions.

What are soft pastels?

They are a mixture of pigment mixed with china clay, chalk, other whiteners, a binder and a preservative. When properly made they are firm enough to stay intact, but soft enough to leave a mark on rough paper without your having to press too hard. The binder is watersoluble, which means you can modify a pastel drawing with a brush and water.

Conté carrés are small, harder pastels which you can use to make finer marks, but which don't easily take over thick layers of soft pastel. Oil pastels are very greasy: they lend themselves to bold work, but they can't really be used with soft pastels.

 Why make your own?

1. It can be cheaper if you use a lot: a pastel costing over £1 may only have 5 pence worth of materials, especially if it is a pale one, which is mostly chalk and clay.
2. You can make the colours you want. Pastels from the big manufacturers look beautiful in their boxes, but the colours are not subtle, and you have to do a lot of mixing on the page if you want natural-looking landscapes or portraits. You never seem to have quite the colour you want in a selection. I must say that this criticism doesn't apply to Unison pastels: they give the amateur maker a target to aim for.
3. You can choose your pigments to be absolutely permanent. The non-toxic non-Cadmium reds do tend to fade a bit, and some manufactured pastels are quite fugitive.
4. You can adjust the hardness or softness, grittiness or silkiness, by varying the proportions of fillers and binder. Even big makers can produce concrete pastels at times.
5. If you want to do something arty, and don't feel like painting, this is the next best thing.
6. It's a good excuse to get messy, though you should try your best not to.

What materials do you need?

Ingredients

1. Pigments, obviously. Suppliers: I got mine from Cornelissens (see above) but you can also go to Jacksons or Great Art. I discuss pigment properties in more (much more) detail below.
2. Precipitated chalk: a fine white powder which bulks out the crayon, and can be used to make a paler pastel (from Cornelissens, too).
3. China clay: makes pastels soft and silky. A pastel that's all chalk can be a bit gritty. You need to adjust the ratio between china clay and chalk depending on the main pigment, especially in the more concentrated crayons. Try to find a local supplier (possibly a potter): the stuff is very cheap, but the carriage is horrendous.
4. A binder. The traditional binder is gum tragacanth, but I use carboxy methyl cellulose. The earth colours can dry quite hard and may need no binder – indeed, one batch of yellow ochre I used set like concrete.
5. A preservative. I use a tiny concentration of Acticide. Keep wrapped in foil in the dark.
6. Water.

Equipment

1. Old newspaper to cover the worktop and to roll the pastels on.
2. A sheet of glass to mix on.
3. A palette knife.
4. A pipette or dropper.
5. Measuring spoons, not to be used in the kitchen. They will probably be 15 ml (tablespoon), 7.5 ml, 5 ml (teaspoon), 2.5 ml and 1.25 ml. A balance weighing to 0.1 g would be great, but you can manage without.
6. Containers for the pigment and solutions of binder.
7. Little trays to dry the pastels in. I use small plastic tomato trays from the supermarket, lined with corrugated cardboard.
8. Safety equipment: a big box of disposable gloves and a dust mask.
9. Somewhere safe to dry the pastels: I find they dry overnight in the airing cupboard without cracking. (I can't always wait until after breakfast to try them out.)
10. A notebook and pencil, to write down EVERYTHING you do.
11. A fine point (your old school compass?) to stipple reference numbers on each pastel.

Getting started.

Try to get used to the materials by making white pastels at first. As most pastels contain more filler than pigment, this will stand you in good stead for the future.

1. Make up a stock solution of binder + preservative. First, add 1 drop of Acticide preservative to a litre of water, label it (it's toxic) and keep it safe. Use this to make up each solution below. These will do to get you started, but you can make stronger or weaker solutions according to your requirements,
   • 0.5% solution: Add 2.5 ml (half teaspoon) carboxymethyl cellulose to 500 ml (half a litre, or about a pint) of water + preservative.
   • 0.25% solution: Add 1.25 ml (a quarter of a teaspoon) to the other 500 ml water + preservative.
   I generally start with the weaker solution. If the dry pastel crumbles, then regrind in more of the same solution, which will double the quantity of mc. You will then know to use 0.5% next time.
2. Measure out 5 ml china clay and 5 ml chalk into a small container, mix together and empty into a heap on the glass sheet. Make a dent in the middle and with the pipette add water drop by drop as if making Polyfilla. Mix with a palette knife, and keep adding 0.25% methyl cellulose (mc) solution slowly until you get a paste that can be rolled into a ball that doesn't crack, but isn't sloppy and holds its shape. Count the number of drops as this will speed up further mixings.
3. Roll out into a pastel shape on newspaper (this will absorb any surplus water.) You can make them any shape you like: cigarette-shaped, cigar-shaped, triangular, square. Prick a serial number on the side, and put on a tray to dry in the airing cupboard.
4. Now it's time to get into the fun stuff: pigments.

What pigments do I need?

Your choice of pigments depends on what images you are going to make. If you are a floral artist, you probably won't need to make any bright, "pure" colours as they are readily available, but you probably will need better greens. The landscape painter will need these greens, and also earths and tinted greys, and very dark colours too.

Artists are always taught to mix as few colours as possible in their paintings, in order to achieve a unity – so why do we need so many pastel crayons? Well, we only need use a few pigments, but as pastels are difficult to mix on the paper, we have to do most of the mixing during manufacture. There are four mixing processes:

1. Hue: mixing pure pigments to achieve the right "colour" e.g. yellow and green to make yellow-green.
2. Tints: mixing filler and white pigment with pigment to achieve increasingly paler pastels.
3. Shades: mixing black with pigment (and filler) to achieve duller, darker colours. It is not easy to get really deep tones in pastel. Unlike watercolours, pastels are not "killed" by adding black.
4. Tone: mixing pigments with black and white to achieve greyed colours. You can get some nice, subtle browns for distances this way, using earth colours. 

Pigments respond differently when wetted to make pastels – I have only used a few of the many available. Here is a table with my findings:

Pigment	Colour	Characteristics and uses	*Methyl cellulose %
Zinc white		A weakish white; useful for making strong tints of weak colours	0.5
Titanium white		Reputedly a cold white, but one which I use as a standard, since the china clay has a slight buff tinge.	0.25
Ivory black		Surprisingly gritty but a very dense black. Useful for the darkest greens and browns.	0.25
Mars black		A manufactured iron pigment, actually a very dark brown, but lovely and smooth to work with.	0.25
Yellow ochre		A natural earth; the sample I had set like cement even without binder. About 10% mixed with other colours is tolerable.	0
Mars yellow		Rather like yellow ochre, but brighter and, being manufactured, lacking the clay. Nice to handle.	0.25
Red ochre		A red version of Mars Yellow, and with it makes a range of attractive subdued oranges.	0.25
Indian red		A purply-red earth, which makes subtle raspberry pinks in tones, and excellent warm browns and greys for distances.	0
Cadmium yellow		Intense yellow, but possibly hazardous if handled thoughtlessly. A strong colour, so  little goes a long way.	0.5
Chrome green		Chromium oxide is a strong, dull green used for camouflage paint, so it must be a convincing colour for landscapists. I mix this with cadmium yellow, mars yellow and ultramarine to achieve all the greens I need.	0.5
Ultramarine blue		In dilution, makes a useful sky colour, perhaps with a trace of phthalo blue. Difficult to handle in strong tones as it collapses into a dense, slippery mass when wetted.	0.5
Phthalo blue		Incredibly strong colour, water-repellent. To use: dissolve in alcohol (methylated spirits, not oily surgical spirits) on the glass, then take up in china clay, chalk and water, (ratio 1 pigment: 10 filler), mixing well. When dry, crush and use like any other pigment: it will still be pretty strong.	0.5

* Concentration of methyl cellulose for strong tints;
pale tints are mostly filler and white, and should be OK with 0.25% mc

Suggestions for mixing

Tints

As we have seen above, tints are made by mixing coloured pigment with white. My standard, most concentrated pastels are made by combining one volume of colour with one of "CCPC" (a mixture of equal volumes of china clay and precipitated chalk). I call this "full tint" or Tmax.
    Paler tints are made using "CCPCTi₂" which is a mixture of 1 vol CC + 1 vol PC + 2 vols Titanium White. (Titanium White is a "stronger" white pigment than CCPC alone.) As a starting point, try the following

• 4 vols CCPCTi₂ + 1 vol pigment, giving a 20% pigment loading (I call this "tint 20" or T20).
• 19 vols CCPCTi₂ + 1 vol pigment, giving a 5 % loading (T5).

1. Make a "Tmax mixture" of 1 vol pigment + 1 vol CCPC, and pile it on the glass sheet.
2. Take half of Tmax for making pastels in the usual way.
3. Take the other half of Tmax and mix thoroughly with 1 vol CCPCTi₂; use half of this new mixture to make pastels – to a reasonable approximation this will be a 25% tint (T25).
4. Take the other half of T25, and add 1 vol CCPCTi₂ to give T12.5
5. Carry on as above to give T6, T3 and so on.

Shades

Shades are made by adding black to pigments. We have the choice of two blacks: ivory black , which is capable of making very dark shades, but is rather gritty in use (even when mulled) and mars black, which is smoother but really a dark brown, so more useful for moderate, warm, shades than deep, cool ones. For a start, try the following:

• Mix 2 CCPC + 1 pigment +1 black (= Bk50).
• Mix 2 CCPC + 0.2 pigment + 1.8 black (= Bk90).

The very deep shades are actually tinted black, and I wouldn't be without them.

Colours

The possible combinations of pigments with eachother and with white and black must number in the thousands. I've made over 400 so far, and I've only scratched the surface.  Below I list some mixtures that I have found useful for landscape.

• The abbreviations are:
• IR = Indian red
• RO = red ochre
• MY = Mars yellow
• CrO = chrome oxide green
• CdY = cadmium yellow
• UM = ultramarine
• PhB = phthalo blue (a 10% mixture in CCPC , made as described in the table above)

• 3MY + 1 RO: rather like burnt sienna; in tone (i.e. with white and black added) makes good bracken colours.
• 8MY + 1 RO: dull, burnt orange; makes flesh tints in pale tints (T5), and bracken tones.
• 16 MY + 1 RO: approaching raw sienna; good for warm skies (T5).
• 10 MY + 1 CrO: tawny green, good for dying grass.
• 3 MY + 1 CrO: poor grass in sun.
• 1 MY + 1 CrO: shaded grass.
• 4 CdY + 1 CrO: sunlight grass, bright.
• 1 CdY + 1 CrO: emerald green.
• 1 CdY + 4 CrO: shaded grass.
• 1 CrO + 1 UM: bluey green, good for some conifers.
• 1 CrO + 2 PhB: a lovely turquoise for skies in pale tints (T10, T5).
• 10 UM + 1 RO: dull violet to subtle lilac (T10).
• 2 UM + 1 IR: dull purple to warm grey (T10), good for distant heather-covered hills.

Size of pastels

A small pastel using about 5 ml dry materials is very useful for taking in the field. This is also a useful size when experimenting, as you don't use too much material.

Commercial pastels are about 12 - 15 ml, which is approximately equivalent to 15 – 20 ml dry materials.

---

Footnotes

1. Colour terms

If you play around with colours in Adobe Photoshop or other applications, you'll find that one model of  colour description is hsb, or hue, saturation and brightness. To find out how this model relates to tints, shades and tones, please read this article.  

2. Your experiences

Have you had a go at pastel making? How did it go? Why not write to us?

3. And, finally …

Now for the best part: making pictures with your own, homemade pastels. Good luck! 

Harry Thomas. File last edited 13 Dec 2006.