With their portability, richness of colour and possibilities for gestural mark-making, oil pastels and oil sticks share many attributes. But understanding their unique characteristics allows the artist to fully realise their potential.
Oil Stick vs Oil Pastel Qualities Explained
What are oil sticks?
Oil sticks (also known as oil bars and pigment sticks) are composed of pure pigment, a drying oil (such as linseed or safflower oil) and a small amount of wax which allows the paint to be moulded into a cylindrical bar. They will dry and cure like oil paint and are fully compatible with traditional oil painting techniques. Almost any fine art support is suitable including canvas, paper and wooden or aluminium panel. However, the surface must first be primed with acrylic gesso or oil primer to prevent the oil leaching into the support and compromising the longevity of your artwork. There are also prepared papers and universal or oil primed canvases and panels which can be used immediately.
Designed to be held comfortably in the hand, Oil Sticks can be used as a drawing tool to apply rich colour directly to the surface and this immediacy offers a different approach to oil painting. Whether used for the initial gestures to sketch out a composition or for the addition of accents and highlights on a more developed piece, the application of colour is directly in the artist’s hand. A light touch will make a crayon-like line, and a hard touch will produce thick, painterly marks. Once the colour has been laid down, it can be manipulated with a palette knife or a brush or extended with an oil medium. Dipping the stick directly into linseed oil before using achieves a wonderfully soft and luxurious mark.
Each brand varies in composition and handling properties; R&F Pigments Sticks are loved by many artists for their lipstick-like consistency, and you will find that they are softer than their Sennelier counterparts. Sennelier also include a small amount of siccative (a drying agent) in their oil sticks, whereas R&F Pigment Sticks do not contain any additives so you can expect longer drying times (bear in mind that the drying time will vary depending on the pigment used).
Sennelier and R&F both produce a colourless medium in stick form which can be used to create glazing effects, add body and blend colour. In addition, R&F also offer the blending medium in large jars which can be applied impasto with a painting knife. They also offer a medium with an added cobalt siccative to accelerate the drying time. Just like an oil painting, an artwork made using oil sticks should be allowed to dry and cure for at least six months before applying a final varnish.
Oil sticks require very little special attention when storing, but it is important to keep them away from sources of heat. They will form a thin skin after being exposed to the air which must be removed before each use, this can be done by dragging the end of the stick along a hard surface to remove the dried film. Oil sticks that haven’t been used for a long time may be a little more stubborn and require a blade to remove the outer layer. However, the paint will still be fresh and buttery underneath.
What are oil pastels?
Oil pastels are made with pigment, wax and a non-drying oil, and their oil content is considerably lower than oil sticks. Because the wax binder is inert, unlike drying oils used in oil paint and oil sticks which eats into paper and canvas, oil pastels can be used on a range of surfaces including wood, paper, canvas and metal without any preparation, making them an appealing choice.
This immediacy lends itself to both preparatory sketches and developed work. In contrast to oil sticks, without the presence of a drying oil the pastels will not cure and harden by oxidation and will remain workable indefinitely. Oil pastels will remain sticky and vulnerable to smudging if not protected by glass. If transporting or storing work, the surface should be protected by glassine paper, a smooth, grease-resistant paper, to prevent damage to the fragile pastel film. An oil pastel fixative, usually based on acrylic resin and alcohol, can help protect against smudging and dust accumulation and can also be used to fix colours between layers before adding more on top. Our own tests have found that oil pastel fixatives vary in effectiveness and some give a gloss or a matt finish; for example, the brush-on Sennelier Pastel Fixative was more successful at preventing smudging and gave a glossier finish than it’s aerosol equivalent. A fixative may not completely set the work so it’s recommended to still use glassine paper when storing or transporting your artwork.
Colour can be applied directly to the support and diluted with turpentine or mineral spirits for a painterly blending effect. Oil pastels are also ideal for adding highlights and reinforcing details on dry oil and acrylic paintings. Because they remain movable they make an unstable base for subsequent layers, however when oil pastels are used underneath watercolour or dilute acrylic, the pastel’s waxy binder will act as a resist. Try adding a detail or a highlight to a watercolour painting; you can be confident that the mark won’t be lost in subsequent washes and the colour will remain strong and bright. Similarly to oil pastels, oil sticks can be used for resist techniques but it is important to work on a substrate that will work with your chosen materials (i.e absorbent enough for watercolour yet able to withstand applications of oil without rotting over time. An acrylic-based watercolour ground would work well for this).
Oil sticks are measured in milliletres and priced according to series numbers, just like traditional oil paints. Some sets are available from both R&F and Sennelier, but you may choose to purchase colours individually according to your particular palette. Oil pastels are considerably cheaper than oil sticks per unit because they are very small, typically, an advantage for artists who enjoy having a wide range of colours, however, you are likely to go through them far more quickly than the larger sized oil sticks.
As well as single pastels, there are many sets to choose from which are either a general assortment of colours, or assembled in themes such as landscapes or portraits.
In conclusion, oil pastels and oil sticks can each be used to their particular advantages. An artist who enjoys the immediacy of oil pastels but wants the finished artwork to have the permanence of an oil painting might find that oil sticks are a rewarding alternative. For oil painters, oil sticks offer a gestural, hands-on approach to traditional oil painting. However, there are considerations which must be taken into account when mixing them with other media. Oil pastels are not subject to as many restrictions, because you don’t need to prep most surfaces or worrying about them eating into surfaces, this makes them a versatile addition to the toolkit of artists working in all mediums.
Use the links below to view the materials mentioned in oil stick vs oil pastel:
Most colours available only in 38 ml, but ivory black and titanium white are available in 96ml
Most colours available in 38 ml and 100 ml except titanium-zinc white and neutral white, which are available in 118ml