Why is graphite soft and slippery?

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A labeled diagram of the periodic table entry for carbon, showing its atomic number 6, symbol C, electron configuration, atomic weight range, solid physical state, hexagonal crystal structure, and weakly acidic oxide properties. Color coding and icons indicate it is a nonmetal, solid at room temperature, with hexagonal structure and weak acidity. — carbon Carbon and its properties.

Graphite is soft and slippery because of its unique crystal structure, which consists of parallel layers of carbon atoms. Within each layer, the atoms are arranged in fused hexagonal rings with strong covalent bonds.1

However, the distance between these individual layers is relatively large, which prevents strong localized bonding between them. Instead, the layers are held together only by weak van der Waals interactions. Because these interlayer forces are so weak, the layers can easily slide over one another. This ability to slide is the direct cause of graphite's characteristic softness and lubricity.1