• Colored Glass

    The manufacture of glass in the old days was based on the use of untreated natural materials — sand, ash, soda, and poor and polluted minerals. As a result, the glass was often cloudy and full of inclusions. The recipe for clear glass was known in antiquity, as evidenced by the antique vials and balsamaria, including color. In the Pompeii frescoes, we see completely transparent dishes with fruits. But right up to the Middle Ages, when stained-glass windows are getting more and more widespread, there are no samples of glassmaking that expressly possess these properties.

    Ordinary glass mass after cooling has a yellowish-green or bluish-green shade. Glass can be colored if, for example, oxides of certain metals are added to the mixture, which, during the cooking process, change its structure so that after cooling the glass will highlight certain colors from the spectrum of light passing through it.
    Colored Glass
    Colored Glass

    Ferrous compounds paint glass from bluish-green and yellow to red-brown, manganese oxide from yellow and brown to purple, chromium oxide to grass green, uranium oxide to yellowish green (uranium glass, often with green fluorescence ), cobalt oxide - in blue (cobalt glass), nickel oxide - from violet to gray-brown, antimony oxide or sodium sulfide - in yellow (colloidal silver paints in the most beautiful yellow), copper oxide - in red (the so-called copper ruby unlike of the gold ruby, which is ​​received by the addition of the colloidal gold).
    Stained-Glass Window
    Stained-Glass Window

    Bone glass is obtained by clouding the glass melt with a burned bone, and milk glass is obtained by adding a mixture of field and fluorspar. Using the same supplements in a very little quantity they obtain opal glass.

    The development of stained glass art is connected with the receipt of the transparent colored glass of a given shape. Another well-known type of colored glass is mosaic smalt, often of manual cooking, irregular shapes, various shades and degree of muffled. Classic examples of the use of smalt are the decoration of Byzantine temples and architectural ensembles of Samarkand.
  • You might also like