Theory:

Have you ever wondered why we cook with aluminium vessels rather than plastic? Why are we making slippers out of plastic rather than iron?
 
Every object has its own set of unique properties and features. We make use of those objects based on their characteristics. So, let us now look at some of the common properties of the materials we are surrounded by.
 
What are the properties of materials?
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Properties of materials:
 
1. Appearance
2. Hardness
3. Soluble or insoluble
4. Objects may float or sink in water
5. Transparency
Appearance
The materials that surround us appear to be different from one another. For example, plastic bottles are not the same as steel or iron bottles. Likewise, the paper we use has a different appearance than the wood.
 
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A plastic tumbler is not the same as a steel tumbler
 
We may divide materials into two categories based on their appearance:
 
1. Materials with shiny or lustre appearance
2. Materials with dull or no lustre appearance
 
Materials with shiny or lustre appearance:
Lustre materials are usually glowing or bright in appearance. Materials such as silver, gold, diamond, iron, copper have a shiny appearance.
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Lustre appearance: gold, diamond and silver
 
Some materials like iron and copper might lose their shiny due to air and moisture on their surface. But when these materials are taken out from the ground, they carry a shiny appearance.
 
Materials with dull or non- lustre appearance:
The word "no lustre" refers to materials that appear dull or non-shiny.
The materials we use in our daily life
 
Examples: Wood, paper, plastic, rubber, cotton, etc.
 
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Non-lustre appearance