In Lesson 3 we started looking more closely at oxides which are found in glass or glaze. We noted the role that certain oxides play in the forming of glass through the heating of raw materials and we learned that to melt our 'glass-former' SiO2 at a temperature lower than silica's melting point we need oxides which will 'flux' the silica. Finally we noted the need to slow down the melting process with oxides categorized as 'stabilizers' or 'modifiers' that expand the melting range so that the melting silica does not run off vertical surfaces.
An examination of the analyses of raw materials used in making glazes showed that each contributed one or more of these essential types of oxides needed for the production of glass or glaze.
This this lesson we will continue our examination of oxides and their role in the making of glass and examine how the balance of oxides of particular types determines the amount of work-heat required to melt the glass-former silica.
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New Zealand Email: lawrenceewing8@gmail.com
In Lesson 3 we started looking more closely at oxides which are found in glass or glaze. We noted the role that certain oxides play in the forming of glass through the heating of raw materials and we learned that to melt our 'glass-former' SiO2 at a temperature lower than silica's melting point we need oxides which will 'flux' the silica. Finally we noted the need to slow down the melting process with oxides categorized as 'stabilizers' or 'modifiers' that expand the melting range so that the melting silica does not run off vertical surfaces.
