๐ Inventions and machines ๐งช Materials and safety
Glass
๐ In short
Glass is a hard, clear material and one of the most useful in our lives. We make windows, drinking glasses, bottles, mirrors, spectacles and phone screens from it. And the amazing thing is that it's made mainly from sand!
๐คฉ Did you know?
- The first glass containers were made about 3500 years ago.
- The biggest glass furnaces melt hundreds of tonnes a day.
- Damascus was once famous for its decorated glass.
- The optical fibers that carry the internet are made of very thin glass.
๐ Find out more
๐ From sand to glass
Sand is mixed with other materials like soda and lime, then melted in a very hot furnace until it becomes a glowing liquid. Then it's shaped and left to cool, becoming hard, clear glass.
๐ Glassblowing
A glassblower can take a lump of hot, soft glass on the end of a long tube and blow into it as we blow up a balloon, turning it into a cup or a beautiful vase.
๐ก Colored glass
When some metals are added to glass it turns blue, green or red. Muslim craftsmen decorated mosques with colored glass windows and made wonderful decorated glass lamps.
๐ฏ Recycle it
Glass can be recycled many, many times without losing quality, melting it down to make new things. So put glass bottles in the recycling bin.
๐ธ More pictures
๐งฉ Test yourself
1 What is the main material glass is made from?
2 Can glass be recycled?
3 The first glass containers were made about ?? years ago.
4 Which picture shows โGlassโ?
๐ Discover more
๐ท Picture sources: Wikimedia Commons
- Ansgar Koreng ยท CC BY 3.0 de
- H. Raab (User:Vesta) ยท CC BY-SA 3.0
- Wikimedia Commons ยท Public domain
- Fah112778 ยท CC BY-SA 3.0
