Glass
Look around the exibhition and see how many types of glass
you can identify
Optical glass
A high qualtiy glass used in optical decvices such as telescopes,
binocular and glasses.
Soda-lime Glass
Contains 70% silica, 15% soda and 9% lime
Its used in windows, jars, bottles, kitchen ware and laboratory
equipment as it is chemically inert (doesnt react with most
chemicals).
Float glass
A sheet of glass made by floating molten glass on a bed of
molten metal.
Blown glass
Melted glass is placed at the end of a hollow rod, the rod is
blown into and the glass at the end forms a bulb.
Fused glass
Different pieces of glass are melted beside eahc other in the
kiln and are fused together.
Sand blasted glass
Sand, walnut shells, steel git, powdered abrasives or coconut
shell are blasted out of blasters gun to etch the surface of the
glass
Diamond etched glass
A diamond is used to scratch the glass to add detailed designs
or texture.
Mould blown glass
Glass is blown into a mould, this allows pieces to be produced
in larger amounts faster with more detail.
What colours can you see?
Glass is coloured by adding metal particals to the molten glass.
Gold = reds and pinks
Silver = yellow
Copper = blues and greens
What way do the pieces use light?
Do they use
 Natural light
 Artifical light (light boxes)
Do they cause
 Shadows
 Reflection of light (bouncing back of light)
 Refraction of light (bending of light)
Did you know?
 15 years ago volkswagon made a life-sized vw beetle
out a solid glass. If glass is cooled too rapidly it wills
shatter, so to avoid this the beetle was kept in a kiln
for 7 years with its temperature being reduced by
thousanths of a degree each day.
 When glass is formed naturally it is called obsidian, it
is created when certain rocks are melted then cooled
and solidified quickly, this can happen as result of
lighting strikes, volcanic erruptions and meteorites.
 Obsidian was used by stone age men on spears and
cutting tools but is now used today by surgeons as
they cut better then scapels.
Which piece appeals to you most?
Why do you think it is interesting?