For example, adding copper to glass can make it blue, while adding tin can make it white.

VOA: special.2009.09.16

Adding chemicals to the glass can give it different color intensities and effects.

VOA: special.2009.09.16

For example, lightning can create tubes of glass when it strikes sand that has the right combination of minerals.

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And,he likes to work near the other glass artists in the school because they can exchange ideas and methods.

VOA: special.2009.09.16

But here,the many objects are stored behind glass so the public can explore the Met's rich collection of historical objects.

VOA: special.2010.08.04

One drink equals a bottle or can of beer, a medium glass of wine or a very small glass of liquor.

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The artist can then add a second color of glass to make designs over the first layer of glass.

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At the Smithsonian American Art Museum, you can see a large heart-shaped sculpture made of blown glass.

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The artist can shape the hot glass using metal tools such as jacks, tweezers and shears.

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As you go through the rooms of the exhibit, you can listen to the videos and see back into the courtyard through the glass.

VOA: special.2010.03.03

His electrically colorful and fluid glass works can be seen in museums around the world.

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Or,he or she can place the hot glass on a metal table called a marver to shape the form by rolling it back and forth.

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Impurities in glass such as iron can give it a green or brown color.

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You can enter the glass building and walk downstairs to an underground visitors center.

VOA: special.2010.06.23

The ash clouds include particles of rock, glass and sand that can get into an aircraft's engine and cause it to stall.

VOA: standard.2010.04.17

"Try to see if you can recognize now a glass of good Italian wine.

VOA: standard.2009.11.15