You can make your own chalk pastels with your custom colours. This is a very simple recipe, but there are several for making pastels. The binder ingredient can be different, and some recipes involve no binder at all, just the distilled water. The whiting chalk I am using could be replaced with kaolin or even plaster. Your results will be different so experimentation is needed as always.
Step 1: What you will need
Gum tragacanth ?
non-latex exam gloves
Working with art supplies is often like cooking, using similar tools. It is a good and safe idea to have a specific set of instruments just for your studio and not use what you have in your kitchen!
Step 2: Make your binder
If you have 2 different sized bowls, start with the smaller to mix your binder.
Measure out the amount of distilled water you want, here I have 20 teaspoons of the water as this is a sample recipe.
Dissolve into the water the gum tragacanth in a ratio of 1 part tragacanth to 20 parts water. Therefore here, I am using 1 teaspoon of gum tragacanth.
Step 3: Mix up your binder
This mixture will be the binder for the pastels. Gum tragacanth will likely make a softer pastel chalk versus another binder.
Use your whisk and mix together. The binder will become thick and gooey and form peaks on your whisk, something like meringue.
Step 4: Choose your colour
In the other bowl measure out your chalk and pigment.
These materials are fine powders that can be an annoyance, if you do not have a well-ventilated space, consider using a respirator with a filter for fine particulates.
Here I have used 5 tablespoons of the whiting chalk for a sample mixture. This wil make between 5-8 pastel sticks.
Add your pigment to the chalk. This colour is cerulean blue, and I used 5 teaspoons. This amount of pigment is based purely on what kind of colour you desire. I do not recommened using anything more than a 2 part chalk to 1 part pigment when you are first trying to find your perfect colour.
Step 5: Combine pigment and whiting chalk
Pigments can be deceiving; a small amount can go a long way and a lot can sometimes seem to never be enough. The colour you see with the dry mixture here is what the finished pastel should produce. It will become darker when the liquid binder is added. If there are small clumps in either powder try sifting or breaking them up or you may encounter streaks of intense pigment or of white while using your pastel stick.
Step 6: Combine binder and powder
Add your gum tragacanth mixture to the pigment mixture until the consistency is like dough. The colour is now intense. Add SLOWLY, the dough should be a dry consistency. With the amounts I used here, I had some binder mixture left over.
Step 7: Roll it out
Roll out your dough into pastel-like sticks in whatever size you prefer. They will be easy to handle and quite maleable from the gum tragacanth. Lay them onto several layers of newsprint to dry. I placed newsprint on top of the sticks too.
Please note, pigments are gorgeous, they can also be somewhat toxic. Some colours more so than others. More often than not the more beautiful shades have a higher toxicity (heavy metals). Best to use gloves when handling pigment in this manner as a precaution especially if you are going to try this often.
Another option for making the pastel shapes is to use a left-over tray from a store-bought pastel box to mould your new pastels or use a knife to cut measured sticks. You will have to turn them out onto the newsprint as well. This will help them dry.
Leave for at least 48 hours, or longer if you are in a humid climate.
Step 8: Done
Homemade chalk pastels