category icon AWARDS & TROPHIES
EVEREST elite collection
AWARD PLAQUES
OBELISK AWARDS
GLOBE AWARDS
STAR AWARDS
EAGLE AWARDS
FLAME AWARDS
MOUNTAIN AWARDS
SCULPTURAL AWARDS
BUDGET AWARDS
category icon CLOCKS
category icon PAPERWEIGHTS
category icon GOLF TROPHIES
category icon SPORTS TROPHIES
category icon CRYSTAL GIFTS
category icon VASES & BOWLS

 
Search

Types Of Glass

Nearly all commercial glasses fall into one of six basic categories or types. These categories are based on chemical composition. Within each type, except for fused silica, there are numerous distinct compositions.

1. Soda-lime glass is the most common (90% of glass made), and least expensive form of glass. It usually contains 60-75% silica, 12-18% soda, 5-12% lime. Resistance to high temperatures and sudden changes of temperature are not good and resistance to corrosive chemicals is only fair.

2. Lead glass has a high percentage of lead oxide (at least 20% of the batch). It is relatively soft, and its refractive index gives a brilliance that may be exploited by cutting. It is somewhat more expensive than soda-lime glass and is favored for electrical applications because of its excellent electrical insulating properties. Thermometer tubing and art glass are also made from lead-alkali glass, commonly called lead glass. This glass will not withstand high temperatures or sudden changes in temperature.

3. Borosilicate glass is any silicate glass having at least 5% of boric oxide in its composition. It has high resistance to temperature change and chemical corrosion. Not quite as convenient to fabricate as either lime or lead glass, and not as low in cost as lime, borosilicate's cost is moderate when measured against its usefulness. Pipelines, light bulbs, photochromic glasses, sealed-beam headlights, laboratory ware, and bake ware are examples of borosilicate products.

4. Aluminosilicate glass has aluminum oxide in its composition. It is similar to borosilicate glass but it has greater chemical durability and can withstand higher operating temperatures. Compared to borosilicate, aluminosilicates are more difficult to fabricate. When coated with an electrically conductive film, aluminosilicate glass is used as resistors for electronic circuitry

5. Ninety-six percent silica glass (see: GLASS AND THE SPACE ORBITER ) is a borosilicate glass, melted and formed by conventional means, then processed to remove almost all the non-silicate elements from the piece. By reheating to 1200°C the resulting pores are consolidated. This glass is resistant to heat shock up to 900°C.

6. Fused silica glass (see: GLASS AND THE SPACE ORBITER ) is pure silicon dioxide in the non-crystalline state. It is very difficult to fabricate, so it is the most expensive of all glasses. It can sustain operating temperatures up to 1200°C for short periods.


Browse our Crystal Awards and Trophies, Everest Crystal Awards, Award Plaques, Golf Trophies, Crystal Award Obelisks
Shopping Cart
Your cart is empty.