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

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


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