What is the chemical composition of lecturers chalk?
The main medium used for chalk drawings is Prang Artist/Lecturer’s Chalk, manufactured by Dixon Ticonderoga in Sandusky, Ohio using FDA approved pigment with a calcium carbonate base and clear liquid soap binder. There are 25 colors in 1x1x3 inch square sticks. Lecturer’s chalk is softer and less dense than pastel due to it’s media base calcium carbonate as opposed to the harder gum base of pastel. This soft chalk is specially designed for large format live drawing since it rapidly covers a large. Prang Fluorescent Artist/Lecturer’s Chalk, also made by the same company in seven brilliant day glow colors. They have bright colors in white light and they glow brighter under fluorescent light.
