These are a kind of Soft pastels, available in flat compact pans similar to makeup kits made of very small quantities of binder and more of pigments. These pastels have much less quantity of binder that they can’t be molded into sticks and hence set into pans. In order to apply pan pastels on paper one needs to use special soft tools like brushes, sponges and other tools. 

Reference:
http://www.panpastel.com/  


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