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Properties we use to sort materials

Lustre: shines or dull (metal vs wood)
Hardness: hard or soft (iron vs sponge)
Transparency: see-through, partial, or blocked
Solubility: dissolves in water or doesn&apos;t
Density: heavy for size or light (sinks or floats)

We sort materials by their properties:

Example

An iron knife: lustrous, hard, opaque, insoluble, dense (sinks).

💡 Tip:Different jobs need different properties. A window needs to be transparent. A pan needs to conduct heat.