Glass
Composition
Properties
History
Production
What is Glass?
•
Glass is a state of matter, not a
substance.
•
Glass combines some properties of
crystals and some of liquids but is
distinctly different from both.
•
Glass has the mechanical rigidity of
crystals, but the random disordered
arrangement of molecules that
characterizes liquids.
•
Glass are usually formed by melting
crystalline materials at very high
temperatures. When the melt cools,
the atoms are locked into a random
(disordered) state before they can
form into a perfect crystal
arrangement.
What is in glass?
• Silica (sand)
• Anhydrous Boric Acid
• Anhydrous Phosphoric Acid These
include:
• Soda Ash
• Potash
• Lithium Carbonate
• Limestone
• Litharge
• Alumina
• Magnesia
• Barium Carbonate
• Strontium Carbonate
• Zinc Oxide
• Zirconia
Properties of Glass
When created properly, glass can be:
Strong resists breaking when it has few surface imperfections & is cooled
slowly
Hard surface resists scratches and abrasions.
Elastic gives under stress - up to a breaking point - but rebounds exactly to
its original shape.
Chemical Corrosion-Resistant
Thermal Shock- Resistant
Heat-Absorbent
Optical Properties
Electrical Insulating
The History of Glass
– When it was discovered
– How it was discovered
– Where it was discovered
– What its first uses were
Discovery
• Natural glass, obsidian, is formed by
volcanoes and has been used since the
stone age for tools
• Glass was discovered by accident as part
of the copper smelting process in 1000 b.c.
in Phoenicia (modern day Lebanon)
• Glass was first used as beads in jewelry
Ancient Glass vs. Modern Glass
The chemical composition
of glass has not changed much
since ancient times
In Ancient Rome…
Glass was so
precious, the
emperor Nero
paid $500 dollars
for one goblet!
The Island of Murano, Italy
• During 13th century
Venice became the
center of
glassblowing. For
safety, and to keep
the process secret,
the furnaces were
moved to the Island of
Murano, off the coast
of Venice
Millefiori – A thousand Flowers
Renaissance to Modern Day
• Glassblowing was a dying Art. Mechanized
processes overtook the hand-blown quality
of the art
• During the 1960’s there was a rebirth of
the Art Glass movement.
• Art Glass is increasingly popular since that
time.
Dale Chihuly
a modern master
“Teamwork suits me.
This is the way artists like
Michelangelo worked.”
Dale Chihuly
Venetian Vases
• With the assistance of
Lino Tagliapietra
United States,
Seattle, Washington,
1988
Blown and hotworked
H (tallest) 44.9 cm
89.4.9
Learning to Blow Glass
• A glassblower is
also called a
“gaffer”
Materials
• Glass “cullet” is melted in the furnace
• Frit – different shapes and colors of
glass added for interest, color and
texture
Tools
• The “punti” a long steel rod used to
manipulate the glass
• The “blow pipe” used to actually blow
the glass
• Molds – used for shaping the glass
The Finished Products
Where can I go to learn to blow
glass?
• Belle Meade Hot Glass – Belle Meade, NJ
• Hot Soup – Philadelphia, PA
• Corning Glass Museum – Corning, NY
• Glassblowing.com – Poughkeepsie, NY
Resources
http://www.historyforkids.org/learn/science/glass.htm
http://www.eastfallsglass.com/
http://glassevolution.com/index.php
http://www.museum.state.il.us/exhibits/barker/gallery/index.php?RollID=group
01&FrameID=Ac164273closmille
http://www.cmog.org/
www.chihuly.com
The End