Pastels are an art medium that many people are familiar with, but there is often confusion about what exactly they are made of and how they differ from other drawing tools like chalk or crayons. In this article, we will explore the composition and manufacturing process of pastels to better understand what sets them apart.
What are pastels made of?
Pastels consist of pure powdered pigment combined with a binder. The pigments used are the same as those used for other colored art media like oil paints or watercolors. The binder is what sets pastels apart from chalk and what gives them their distinctive soft, crumbly texture.
There are two main types of pastel binders:
- Gum binders – These use gums like gum tragacanth or gum arabic to bind the pigment particles together. Gum binders produce a soft, crumbly pastel.
- Resin binders – These use materials like pine resin or vinyl resins as the binding agent. Resin binders yield harder, waxier pastels.
In addition to pigment and binder, pastels also contain filler materials such as calcium carbonate or kaolin clay. The filler gives the pastel strength and stability without making it too hard. Soft pastels contain more filler than hard pastels, resulting in a chalkier, crumblier texture.
How are pastels made?
Pastels are made through a fairly elaborate manufacturing process that results in their distinct consistency:
- The pigment powder is mixed with the binder, filler, and any wetting agents or preservatives.
- The paste is rolled into sheets and allowed to dry.
- The dried sheets are broken into small pieces and sorted into bins of similar colors.
- The pastel pieces are packed into wooden or cardboard sticks and allowed to harden into the final pastel form.
Making the initial pigment-binder paste and shaping it into sheets requires industrial equipment. But many artists will re-shape broken or worn pastel pieces into new sticks by hand to get more use out of them.
How do pastels differ from chalk?
While pastels are similar to chalk in appearance, they differ in a few key ways:
| Pastels | Chalk |
|---|---|
| Made from pigment powder mixed with gum or resin binder | Made from calcium sulfate with no binder |
| Available in a vast array of colors | Limited color range |
| Soft, crumbly consistency | Hard, dry consistency |
| Create richer color with more blending | Drier, lighter color application |
| Used for fine art drawing | Used for sketching, writing |
The main composition difference is the use of binder in pastels. Chalk is simply calcium sulfate, the same main component as gypsum drywall. With no binder holding it together, chalk has a hard, dry texture that produces dusty, pale lines. The binder in pastels allows for richer pigmentation and smoother blending.
Pastels also contain a wider variety of pigments than standard classroom chalk, resulting in a much broader color range. Mixing and layering these colors allows artists to achieve complex gradients and hues.
What types of pastels are there?
There are a few major categories of pastels:
- Soft pastels – These contain more filler and less binder, resulting in a soft, crumbly stick that produces thick, velvety strokes of color. Soft pastels are great for blending.
- Hard pastels – With more binder and less filler, these are firmer and waxier than soft pastels. Hard pastels produce sharp, fine lines with no smudging.
- Pastel pencils – Powdered pastel pigment is mixed with wax and encased in a wood casing like a pencil. These are excellent for detailed drawing.
- Pan pastels – The pastel pigment is shaped into small flat pans like eyeshadow. Users apply the colors using a special applicator sponge.
Artists can choose the type best suited to their style and subject matter. Many utilize a combination of soft, hard, and pencil pastels in one work.
What is the history of pastels?
Pastels have been around as an artistic medium for centuries, with their composition and manufacturing techniques evolving over time:
- Indigenous South American peoples used crushed mineral pigment mixed with animal fat to make early pastels.
- Soft pastels using gum binders were developed in Renaissance Italy, allowing greater color intensity.
- 18th century pastellists like Rosalba Carriera pioneered new pastel techniques.
- Mass manufacturing in the 19th-20th centuries made pastels widely available and affordable.
- The 20th century Impressionists often used pastels in their work.
- Modern materials like mineral spirits allow faster drying and fixation of pastel art.
While pastels have been used by artists for hundreds of years, new applications and types are still emerging today alongside other color media.
Why are pastels popular with artists?
Pastels offer artists a number of unique advantages:
- Vibrant colors – Less binding medium results in denser, more saturated color than paint.
- Easy blending – The soft, crumbly texture makes smooth color gradations easy to achieve.
- Immediate application – No mixing or preparation is required allowing direct application to the surface.
- Versatile effects – Lines, shading, blending, hatching, and many textures are possible.
- Compact and portable – Pastels are easy to carry and travel with.
- No drying time – Drawings can be completed quickly without waiting for layers to dry.
Pastels give artists flexibility, spontaneity, and brilliance of color perfect for quick studies, outdoor sketching, and finished works.
How should you use and handle pastels?
Getting the most out of pastels requires the right techniques and care:
- Choose an appropriate surface – Paper, board, or canvas with some tooth helps grab and hold the pastel pigment.
- Start light and layer darker colors over – It’s difficult to cover up dark pigment with lighter shades.
- Blend with cotton swabs, tissue, tortillons, or your finger – Only blend lightly to avoid over-mixing colors.
- Spray with fixative between layers – This prevents smudging and helps build up color.
- Keep hands and work area clean – Pastel dust can spread and smudge easily.
- Store unused pastels flat in a box – Vertically they risk snapping under their own weight.
With some care and practice, pastels offer artists an unparalleled spontaneity, versatility, and vibrancy of color.
Conclusion
While they may look like simple sticks of colorful chalk, pastels require an elaborate manufacturing process to achieve their characteristic texture and vivid hues. The addition of binders to powdered pigments is key, allowing pastels to be molded into sticks then applied with both sharp definition as well as soft, blended strokes. Their versatility, portability, and brilliance of color make pastels a favorite medium for many artists. By understanding their composition and handling them with care, anyone can use pastels to produce professional quality drawings and paintings.
