1. 2010 TCA Juried Biennial: Glass Glorious Glass Tempe Center for the Arts Activities by Mary Erickson, Ph.D., with Arizona art teacher Lynn Allison McGavak-Martin

2. People throughout time and around the world have made and used glass. In the 1400s, Europeans brought glass beads to West Africa, where they traded them for things, like gold, ivory, incense and palm oil.

3. Can you guess where industrious people from Africa get glass to make these beads today?

4. They recycle old glass from soda and medicine bottles to make glass beads.

5. Arizona glass artist, Laurie Nessel, makes glass pieces today using a process first developed more than 3,000 years ago in ancient Mesopotamia.

6. The main ingredient of glass is quartz sand, or silica, with a few added minerals (lime, magnesium oxide and aluminum oxide) that bring down the temperature at which the silica melts. Years of exposure to the sun can cause a mineral in some glass to turn slightly purple, like this piece of desert glass.

7. Old bottles turned purple by the sun.

8. You can see old glass objects like these at the Tempe History Museum.

9. Lots of everyday objects are made of glass - from mirrors, to marbles, to candle holders, to cactus bookends.

10. Windows, walls, doors and even tables can be made of glass.

11. Glass has many wonderful qualities and can be colorful.

12. Glass can take many forms.

13. Glass can have many different textures.

14. Glass can reflect light and let light pass through it.

15. Glass can be transparent, translucent or opaque. transparenttranslucentopaque

16. Transparent glass is clear and you can see through it.

17. Translucent glass lets light pass through, but you can only see foggy outlines and colors through it.

18. Opaque glass does not let light pass through.

19. Which bird is transparent? Translucent? Opaque?

20. Which holiday ornament is made of plastic? Wood? Glass?

21. How can you tell this ornament is made of glass? What feeling does the ornament have because it is made of glass?

22. The Biennial: Glass exhibition at the Tempe Center for the Arts features Arizona artists working in many different glass techniques.