BENEFICIATION
The Eiffel Tower is due to get a protective bullet
resistant barrier to deter terrorist attacks.
the products of this exclusive industry
within the reach of 'the ordinary man in
the street'. The ubiquity of glass on Roman
archaeological sites is testimony to its ability
to span the gap between the disparate
geographical and social elements of the
Roman Empire.
Why do we make glass?
The uses of glass are many and varied,
with each manufactured using a different
technique:
• Glass containers: in which glass is
carefully made in three different stages
(melting of raw materials, pouring
or blowing glass in container moulds
and cooling with finishing touches for
quality).
• Float glass processes: in which glass
is laid on the surface of molten metal
(tin or lead). This process is used for
creating of flat windows.
• Manual glass blowing: used mostly for
creating of art objects and custom glass
containers.
• After manufacture, every glass product
can be additionally treated by coating,
heat treating, engraving or some kind
of decorating.
• Toughened glass: this type of glass is
tempered, may have distortions and
low visibility but it breaks into small
dice-like pieces at modulus of rupture
of 3 600psi. Hence it is used in making
fire resistant doors. They are available
in the same weight and thickness range
as float glass.
• Laminated glass: this type of glass is
made by sandwiching glass panels
within a protective layer. It is heavier
than normal glass and may cause
optical distortions. It is tough and
protects from UV radiation (99%) and
insulates sound by 50%. Used in glass
facades, aquariums, bridges, staircases
and floor slabs.
• Shatterproof glass: by adding a
polyvinyl butyral layer, shatter proof
“Though glass is today one of the most common building materials for windows, as
well as many ornamental objects and computer communications, its initial use by our
earliest ancestors was as a sharp weapon and useful tool.”
34_QUARRY SA| NOVEMBER/DECEMBER 2018