Answered By: Regan Brumagen
Last Updated: Mar 17, 2017     Views: 6796

 

From Dr. Robert Brill, Research Scientist Emeritus:


 

"There are many different kinds of glass.  Glass is best described as a state of matter, not as a compound or mixture having one special chemical composition.  Literally hundreds of thousands of glasses with different chemical compositions have been made, and each of them has its own set of physical properties as determined by its own chemical composition.  Even so, they all share certain properties in common that are the result of their having similar structures at a molecular level.  Glasses combine some of the ordinary properties of crystalline solids with some of the properties of liquids but without being either crystalline solids or liquids.

 

Most glasses that would be familiar to you and your classmates contain certain elements.  These elements are usually described in terms of their oxides.  Those most commonly used are:

 

  • Si, silicon.  The oxide is SiO2, silicon dioxide.  Ordinarily the SiO2 is introduced as sand. 
  • Na, sodium.  The oxide is Na2O.  It is introduced as a white powder called soda ash.
  • Ca, calcium.  The oxide is CaO.  It is introduced as limestone, a mineral.
  • Pb, lead.  The oxide is PbO.  Lead oxide in a glass makes it shiny, brilliant, and heavy.
  • K, potassium.  The oxide is K2O.  Potassium can be used in place of sodium as a "flux", a substance that allows the sand to be melted at a lower temperature.

 

Many other elements are used to make glasses with special properties. For example, the following elements can be used to make glasses with the colors described:

  • Fe, iron.  Colors glass green.
  • Cu, copper.  Colors glass light blue.
  • Mn, manganese.  Colors glass purple.
  • Co, cobalt.  Colors glass dark blue.
  • Au, gold.  Colors glass deep red, like rubies. "
 
Below is information provided by the Rakow Research Library Staff
 

 Compositions of some Commercial Glasses below taken from text: The Properties of Glass by George Morey: The first row at top is Belgian Fourcault. The second row down is European Flat drawn Window Glass, The third row  down is American Flat Drawn window glass, The fourth row down is light Green Bottle Glass,  The fifth row down is Champagne bottle glass.

SiO2

Na2O

K2O

MgO

CaO

PbO

Al2O3

Fe2O2

70.51

16.74

   

10.67

 

1.42

0.16

70.64

17.02

 

0.09

10.58

 

0.77

0.11

72.14

17.02

 

2.62

11.24

 

1.06

0.15

64.3

5.87

2.56

5.61

14.73

 

4.89

1.18

63.18

9.88

0.36

1.12

14.4

 

8.39

1.39

 

 
 

 

Compositions of some Natural Glasses below taken from text: The Properties of Glass by George Morey:  The first row at top is Obsidian from Obsidian Cliffs in Yellowstone National Park, The second row down is Obsidian from Cerro de los Navajo, Tulancingo, Mexico, The third row down is Rhyolite glass, Burton Peak Nevada, The fourth is Rhyyolite glass, New South Wales,  The Fifth row down is Tekite from Peru.

 

 

SiO2

Al2O3

Fe2O3

FeO

MgO

CaO

Na2O

K2O

H2O+

H2O-

TiO2

74.7

13.72

1.01

0.62

0.14

0.78

3.9

4.02

0.62

   

73.92

12.38

1.62

0.56

0.27

0.33

3.49

5.39

1.69

   

71.6

12.44

1

0.65

0.06

1.9

3.3

4.22

3.78

0.81

0.25

70.62

11.54

1.2

0.18

0.26

1.72

3.52

1.42

7.24

2.42

0.04

70.56

20.54

 

0.96

0.11

0.78

3.47

3.38

     
                     

 

 

 

If you'd like to read more about coloring glass, consult the list of books/articles on the topic below: 

Angus-Butterworth, L. M. The manufacture of glass. New York, Chicago: Pitman Publishing, 1948. Note: Chapter 6, "Colours in Glass": pp. 49-63

Bamford, C. Ray. Colour generation and control in glass. Marietta, OH: CBLS, 2002. xi, 224 p.

Reprint of 1977 Elsevier ed. (CMGL owns). Includes bibliographical references and indexes.

Bearer, Rocio. The cookbook of color borosilicate recipes. Volume one, A guide to using Northstar Glass. Rocio Bearer, Ron Bearer Jr., Lori Robbins. [S.l.]: Three Glass Fanatics, [2005] (Titusville, Fla.: Thunderbird Press, Inc.) 62 p.Over 50 color combinations illustrated.

Bray, Charles. “Colour.” Ceramics and glass: a basic technology. Sheffield: Society of Glass Technology, 2000, pp.195-232.

Bray, Charles. Dictionary of glass: materials and techniques. 2nd ed. London: A & C Black; Philadelphia: University of Philadelphia, 2001.Note: Basic introduction to coloring glass, pp. 79-81. See also entries for colloids, oxidation, reduction and Aventurine glass.

“Color in glass.” Glass Art, v. 1, no. 3, June 1973, pp. 12-20. Note: Reprinted from Scholes, Modern Glass Practice.

Conrad, John W. “Glass colorants.”Glass Art, v. 2, no. 4, August 1974, pp. 17-18.

Florian, Robert and Dominick Labino. "The Color of Glass Dictates Form."Craft Horizons, v. 26, no. 4, July/August 1966, pp. 29-31.

Frey, Thomas. The chemistry of glass. San Luis Obispo, CA: the author, 1990.

The glass-making oxides.” Glass Art, v. 1, no. 2, April 1973, p. 14-21. Reprinted from Scholes’ Modern Glass Practice.

Halem, Henry. Glass notes: a reference for the glass artist. 4th ed. Kent, OH: Franklin Mills Press, 2006. pp. 10-14.

Moore, H. Selenium, tellurium, cobalt and nickel in glass making. London: Mond Nickel Co., Ltd., 1956. 40 p.

Morey, George W. The properties of glass. 2d ed. New York, Reinhold, 1954. 591 pp. (American Chemical Society. Monograph series, no. 124).

Neuwirth, Waltraud. Farbenglas: vom Biedermeier zum Art Deco = color in glass: from Biedermeier to Art Deco. Vienna: the author, 1993. 2 vols.  I: Color schemes white, black, yellow, green; II: Color schemes blue, red, index.

Paul, Amal. Chemistry of glasses. 2nd ed. London: Chapman and Hall 1990.Note: Chapter 9, "Coloured Glasses," pp. 276-348.

Pincus, Alexis G.; David H. Davies. Raw Materials in the Glass Industry. New York: Ashlee Publishing Co., 1983. pp. 338-399.Note: Part II: Minor Ingredients.

Pye, L. D.; H. J. Stevens; W.C. La Course. Introduction to glass science. New York; London: Plenum Press, 1972.Note: Includes: Harding, Foster, "The Development of Colors in Glass," pp. 391-431. Also: Beer-Lambert law, p. 400; Laporte’s Rule, p. 401; Ligand Field Theory, pp. 396-417; decolorization, p. 415; effect of temperature, p. 408; striking, p. 424; solarization, p. 422; enery levels, pp. 394-401.

Schmid, Edward T. Ed's big handbook of glassblowing. Jamestown, CO: Glass Mountain Press, 1993. pp. 55-61.

Schmid, Edward T. Advanced glassworking techniques. Bellingham, WA: Glass Mountain Press, 1997. 320 pp.Note: Color: pp. 95-131.

Schmidt, Wilhelm. Recipe book for practical glass melting. [S.l.]: Cider Press, 1998. 152 pp.Note: Batch book. Translation of: Rezeptbuch für die praktische glasschmelze, 1926. Includes bibliographical references. Translated, edited and commented by Finn Lynggaard. "From all kinds of clear-glass batches to coloured batches for under-and-overlay techniques, it also includes such specialties as glass for mine lamps, for battery glasses and for X-ray tubes"-- foreword. Bibliography, p. 151.

Scholes, Samuel R.; Charles H. Greene. Modern glass practice. 7th rev. ed. Boston: Cahners Books, 1975. Note: Chapter 17, pp. 289-331.

Shelby, James E. Introduction to Glass Science and Technology. Cambridge, England: The Royal Society of Chemistry, 1997. xiii, 244 pp. (intro. college text)

Silverman, Alexander. Sandwich glass. New York: Glass Industry, 1936.Note: 1. Introduction and crystal batches. 2. Opal and alabaster glasses. 3. Red and pink glasses. 4. Amber, yellow and green glasses. 5. Blue glasses, pink, lavender and purple, gray and black glasses, as well as methods of silvering glass.Reprinted from Glass Industry, v. 17, 1936.

Simmingsköld, Bo. Raw materials for glass melting. Sheffield, England: Society of Glass Technology, 1997. 74 pp.Note: Revision, editing and additional translation by K.H. Teisen & R.D. Wright. Translation of: Råvaror för glassmältning.

Vogel, Werner. Glass chemistry. 2nd ed. Berlin ; New York: Springer-Verlag, 1994. xiv, 464 p. 
 Weyl, Woldemar A. (Woldemar Anatol). Coloured glasses. London: Dawson, 1959. xvi, 541 p. (Monographs on glass technology) Originally published in 1951 by the Society of Glass Technology, Sheffield.