are great for sketching, detail work, and finished paintings. To make the pigment durable enough to form a lead, the pastel is by necessity a little harder than pastel sticks. There is not a significant variation in hardness between the different brands. Care is required in sharpening due to the combination of soft pastel lead and wood casing - make sure you have a fresh blade in your sharpener. Hand held manual sharpeners with changeable blades or table mount sharpeners with a self feed function are recommended. All pastel pencils are somewhat water-soluble.