Pastels are a very large and often confusing family of art materials, but they are a very versatile medium and are worth getting acquainted with! We'll go over the differences, the similarities, how to identify the quality, plus some tips on preservation (both for yourself and your artwork).
What are Pastels?
- powdered pigments mixed with minimal amounts of some sort of binder
- usually compressed, usually into a stick-like form
What are Pigments?
Pigment powders are used as the base for all paint colours
- oil paint is made by adding pigments to oil
- acrylic paint is made by adding pigments to an acrylic emulsion
- watercolours are made by adding pigment to gum arabic
What's the Appeal?
Because the pigment is not suspended in a fluid binder, pastels offer an unadulterated colour which is closer to the true hue of the natural dry pigments than any other media. Pastels are also compact and easily transportable (ideal for plein air painting), plus they're easy to work and to rework, and in some cases they are erasable too!
Artwork made using pastels is called a 'pastel', pastel drawing, or pastel painting. Pastel is a noun, a verb, and an adjective!
- a pastel: noun: a compressed, stick-like artistic medium; a painting completed in pastels
- to pastel: verb: the act of painting in pastel
- to be pastel: adjective: referring to something as pale in colour
Pastels have been used by artists since the Renaissance, gaining more popularity in the 18th and 19th century when a number of notable artists made pastel their primary medium.
Edgar Degas (1834-1917) frequently used pastels. Degas is probably best known for his pastel portrait work and his series of ballet paintings, many of which are pastel.
TYPES OF PASTELS
Soft Pastels (a.k.a. Chalk)
Soft pastels are often referred to as chalks because a painting done in soft pastels has a loose powdery surface that is easily smudged. Full sized soft pastel sticks are around 2.5" long and could be either round or square sticks (depending on the brand) and some companies offer selections of half-sticks (1.25" long). Soft pastels are generally very brittle and prone to breaking or crumbling.
The highest quality soft pastels are made almost entirely of compressed artist-quality pigments with minor amounts of kaolin clay and a drop of gum arabic as a binder. Kaolin is an extremely fine, velvety-soft clay which imparts a luxuriously smooth talc-like feel when laying colour down.
Lower quality pastels contain low quality pigments (often in a lower concentration) and contain more fillers; including actual chalk (calcium carbonate) instead of of kaolin clay. Because of the addition of fillers, lower quality soft pastels appear less vibrant and are far more challenging when employing a fixative. (Applying fixative over cheap pastels and watching your painting dissolve into oblivion is heartbreaking.)
Hard Pastels (a.k.a. Conté)
Hard pastel sticks were invented in 1795 by Nicolas-Jacques Conté. The Conté name has since become synonymous with hard pastels. They are very similar in composition to a soft pastel with the addition of wax as a binder. As the name suggests, hard pastels are compressed into a very hard stick that is about half the diameter of a soft pastel (square or octagonal in cross-section, never round). Conté is a great companion for soft pastel artists because it keeps a hard edge, allowing the artist to add crisp details to a soft pastel piece.
Conté sticks are still brittle and prone to breakage just like their softer cousins, but due to the addition of wax as a binder, they create a little less dust and are a little less prone to accidental smudging than soft pastels.
Conté on grey or brown toned paper is an ideal combination for quick sketches during life drawing sessions.
Just as the name suggests, these are pastels that look like a pencil; complete with a wood casing around a coloured pigment core. The core composition is closest to that of a hard pastel (with a potentially higher ratio of wax binder in the lower quality brands). Like other dry pastels, pastel pencils are easily blended and smudged, but they are more rugged in terms of traveling to plein air locations. Pastels pencils are ideal for adding very fine detail to a pastel painting and they can be sharpened just like a regular pencil, however it's recommended to get a short cone sharpener.
Using the correct sharpener will help avoid breakage and wastage of your pencil core, saving you money and frustration. If your local art store doesn't carry a short cone sharpener, then head over to a pharmacy and grab a good quality eyeliner pencil sharpener; it's the same thing.
These are soft pastels that are pressed into a flat cake (as opposed to a stick) and sold in a disc-shaped container, complete with screw-on lid. At this point in time, Pan Pastel is the only company making pastels in this format and so the name has become synonymous with the product. The people at Pan Pastel have also introduced a line of miniature palette knife tools with replaceable foam rubber tips. (A cheaper option is to use eyeshadow applicators instead.)
In my personal experience, Pan Pastels are an outstandingly high quality soft pastel, but the palette knife applicator doesn't jive with the way I work. (I really wish they made sticks as well because their colour formulations are magical.)
Modern oil pastels (generally speaking) are a mixture of powdered pigments, an oil, and wax. Full sized oil pastel sticks are around 2.5" long by .25" in diameter and could be either round or square sticks (depending on the brand). They glide across the substrate like a stick of butter and are intended to never dry; remaining smudgy and blendable perpetually. Oil pastels can be further blended by using a cloth or cotton swab moistened with oil paint thinner.
High quality oil pastels will use high concentrations of artist-quality pigments with minimal amount of wax and oil added, resulting in very vibrant colours and a very smooth lay-down.
Lower quality oil pastels contain low quality pigments (often in a lower concentration), much higher ratios of wax, and an inexpensive non-drying oil (sometimes mineral oil). The quality difference can often be seen as soon as you open the package; a low quality pastel may have a foggy or frosty appearance on the outside of the stick. This fog is actually called blooming and is a bad sign; it's an indicator of high concentrations of wax (like cheap Easter chocolate). Low quality oil pastels will also resist layering over one another (again, due to the wax content)
Oil Bars (a.k.a. Oil Sticks)
Oil bars look like giant, expensive oil pastels. Oil bars are only available in artists grade; using high concentrations of high quality professional pigments combined with a fast-drying oil, wax, and in some cases a minuscule amount of solvent. Oil bars are meant to be as close as possible to a solid version of oil paint.
The chief differences to oil pastels
- oil bars will dry over time (just like an oil paint)
- oil bars are enormous compared to an oil pastel
If you've ever bought a new oil bar you may have noticed it had tough skin on it. The skin develops as the oil in the bar dries in the areas exposed to air. Skins can be softened by top dressing the bar with a thin layer of oil and leaving it for a day or two before using it, or you can scrape off the thin skin and there will be supple oil bar underneath.
The "oil pastels" that were used by artists like Edgar Degas and Edvard Munch were closer in composition to oil bars than the oil pastels we know today.
Water Soluble Oil Pastels
Water soluble oil pastels are similar looking and have a similar feel to regular oil pastels, however they are blendable with water instead of solvent. The composition of these types of pastels seems to be heavily guarded secret, however, having used them myself I would say they resemble a stick of margarine; very soft, very slick, cleans up with soap and water, and never dries completely. Like margarine, a water soluble pastel contains a microscopic dispersion of water so when more water is added, it appears to "dissolve" into water.
After comparing it to margarine you'll probably not be surprised to hear that an artist grade water soluble oil pastel doesn't exist; all are non-toxic and therefore not using the highest grade of pigments... but dang, they sure are fun to use!
PROTECTING PASTEL PAINTINGS
Regardless of what type of pastel you've used, a finished pastel painting should not be left unprotected. Here is an outline of some protective options.
A fixative is a topical spray that is applied to a pastel piece to help bond the pastel to it's substrate and to prevent smudging. Workable Fixative enables easy reworking of the artwork. Krylon makes both a Workable Fixative and a Fine Art Fixatif.
- Workable Fixative is intended to be used throughout the pastel painting process, from the ground up
- Fine Art Fixatif is a finishing spray for pastels that contains UV light stabilizers (sun block) and is removable for conservation purposes (for a full explanation of what that means, check out our article Removable: It's a Good Thing)
- Acid free and archival safe
- provide a clear & durable matte finish
- 11 oz. aerosol can
- Ideal for soft pastels, somewhat suitable for oil pastels
The alternative is a non-aerosol pump spray called Spectrafix which is casein (milk protien) suspended in vodka. (Yup, you read that right... vodka.)
The pump delivers a fine mist of alcohol and casein that saturates the soft pastel pigments. When the alcohol evaporates, the casein is left behind holding the pastel pigment in place. Caution should be exercised when using Spectrafix: too heavy of an application will cause colours to run together; it's better to spray in multiple thin layers, allowing layers to dry between applications.
Spectrafix is archival and smells nice and is great for indoor studio use, but be forewarned that it is re-soluble so it's not ideal for mixed media applications.
The Downside of Fixatives
Regardless of what brand of fixative you try, be aware that all fixatives will affect the colour of the pastels to some degree. The painting will never look the same as it did prior to fixing; colours will darken and highlights can disappear altogether, flattening the whole picture. I have a lot of experience with pastels and I've tried so many fixatives. All fixatives alter the original colours to some degree. (I've found that Spectrafix is the least disruptive fixative as far as colour saturation goes. Once dry, the painting looks very close to how it originally was prior to fixing.)
The best solution overall is to spray fixative frequently throughout the painting process (so you can re-work saturated areas as you go) and to use the highest quality pastels possible (this alone will make an enormous difference).
Cold Wax Medium
Cold wax medium is mixture of refined white bees wax and mineral spirits. It's best suited for protection of oil bar paintings specifically and not all all suitable for soft pastels. I've tried using cold wax over oil pastels before and I'm not going to say it didn't work, but it wasn't ideal. Because they never dry, thick applications of oil pastel will remain soft and squidgy under the wax layer. If you're trying this, I recommend spraying the pastel piece with workable fixative before applying the cold wax (to prevent the mineral spirits in the wax medium from smudging the painting).
- once you have a completed and dried oil bar painting
- apply a thick layer of cold wax medium using a palette knife
- allow the cold wax layer to dry and harden into a matte finish
- for a more glossy finish buff with a soft cloth or paintbrush
Keep in mind, this is just a layer of wax on the painting so it's not as durable as a proper varnish layer or putting it behind glass..
Mounting a pastel behind glass really is the best and most traditional protective option, but it's also the most complicated and most expensive option. The complications will arise from choices like what frame design compliments your art, what matting colour to choose, single mat or double mat, and heaven help you if your piece is not a standard size. If your piece is a standard size you may be able to buy a pre-made frame with matting, but your options will be limited. The expensive issues arise from having custom framing done; if your intention is to sell your paintings then the cost of framing can drastically push the cost of your piece up, making it harder to sell.
Do Your Future-Self a Favor
Avoid a framing nightmare ...
4x6" 5x7" 8x10" 9x12" 11x14" 16x20" 18x24"
Almost all soft and hard pastels now come with a scary warning...
"This product contains a chemical known to the State of California to cause cancer."
Do not panic. These are the exact same pastels that we all grew up using in school and we are all still alive and kicking. They aren't adding some new poison and the formulation hasn't changed. What has changed is our understanding of the dangers of Titanium Dioxide when it's airborne.
Titanium dioxide is the pigment most often used as white pigment. This pigment is used in all lighter colours of pastels (especially in the lower quality pastels). Titanium dioxide is also used extensively in cosmetics and candy and other food items because it's safe to have on your skin and it's safe to eat.... It is not safe to inhale.
The worst habit you can pick up is blowing off the excess dust from your painting...
DO NOT BLOW!
If dust is accumulating...
- take the piece outside
- hold your breath (if you're not using a respirator)
- turn the painting upside down and tap the back side
- then vacate the area immediately so you can start breathing again.
If your're using artist quality pastels, it's not just titanium dioxide you have to worry about. Artist pigments are made from heavy metals and other toxic elements such as barium, lead, mercury, arsenic, cobalt and cadmium just to name a few. In case it's not obvious, inhaling this stuff is VERY BAD for you. Your body doesn't flush out these toxic elements, instead they accumulate over time (also VERY BAD).
Get into the habit of wearing gloves
Cheap oil pastels are pretty benign, however artist quality oil pastels will readily stick to your skin like lipstick and are loaded with those vibrant and toxic pigments, so please protect yourself by wearing gloves (or by using a barrier cream at the very least).