Page 5 - Curriculum Visions Dynamic Book

See Vol. 4: Ceramics to find out more about the nature of ceramics.
(Below) Glass is often thought of as being both transparent and brittle. Many modern glasses are not as brittle as their historical counterparts because they have fewer defects in them.
Although it is so well known, glass is actually
a very difficult material to put into any group with other materials. It is made from the same kind of materials that make cement, but it is not a crystalline mineral, or ceramic. It has some of the properties of a liquid (its atoms are not arranged in regular patterns) but also some of the properties of a solid (it is hard and cannot flow).
The uniqueness of the substance we call glass has led many people to put it into a category all of its
own – a special state of matter – a glassy state. Others simply call it a special kind of solid – an amorphous solid, meaning that as it cools from being molten, its atoms lock together in an unorganized way and so cannot form perfect crystals.
5