Corning Museum of Glass

Iridescence
A prism divides light into the colors of the rainbow. The deteriorated surface of some old glass objects has the same effect. Modern glassmakers can create this effect by applying chemicals to the surface of glass.

watch: Making Iridized Glass
In this video, you will learn the causes of both accidental iridescence and that achieved purposefully.

Glass in Nature
Volcanoes spew molten lava. As it cools, lava sometimes turns into glass – a natural glass called obsidian. Other natural glasses exist. For example, irregular glass tubes are created when lightning strikes sand.

Crizzling
The cloudy effect of crizzling in glass is the result of an imbalance in its ingredients. The instability results in an attack by atmospheric moisture, which produces a network of cracks in the surface of the glass. Crizzling can be slowed or perhaps even halted, but it cannot at present be reversed.

listen: Think of Glass as a Cake
listen: Glass Crizzling
Learn more about what causes crizzling and how affected glasses may be safely stored.

Glass and Science
For hundreds of years, glass has been used to make scientific apparatus because it resists the corrosive effects of most substances. From the 17th century, glass has also been used in microscopes, telescopes, thermometers, and barometers.

listen: Alchemical Glass Vessels
Learn why glass was so vital for early alchemical vessels.
explore: Glass of the Alchemists
Learn about the exchange of glass knowledge across Europe, alchemy, and what new types of glass were discovered from 1650 to 1750.

Heat-shaded Glass

Heat-shaded glass is glass that has two colors represented on one object, with one color shading into the other. The glassblower can control which part of the object changes color by inserting only part of the glass into the reheating furnace. For example, Burmese art glass shades from salmon pink to yellow.

watch: Heat Sensitive Glass
See how the glass "strikes" or changes color.

Batch Game
Making different kinds of glass is like baking a cake: if you alter the ingredients, you alter the result. The Batch Game allows you to combine different ingredients to make different kinds of glass.

Borosilicate Glass
Glass that contains the element boron withstands sudden changes of temperature because it expands and contracts very little. This is why it makes excellent cookware and scientific apparatus.

200-Inch Disk
This is the failed first attempt to cast the mirror for the giant reflecting telescope on Palomar Mountain, CA. If the casting had succeeded, the flat side would have been ground and polished. The second casting is part of the Hale Telescope.

Periscope
A periscope contains a system of lenses and mirrors that allows people to see over things and around corners. Periscopes allow sailors in submarines to remain under water while watching activity on the surface.

Prince Rupert's Drop
When a blob of molten glass is dropped into cold water, it cools quickly and forms a solid object with a round head and a narrow tail. The head doesn’t break when struck with a hammer, but, because of internal stress, the drop shatters if the tail is broken or scratched. In this video, you will see evidence of the two kinds of stress in glass –compression and tension.