Assertion: glass's flux | /r/HasProperty | added
Facets:
Source sentences:
text: A flux, usually soda (sodium oxide as 10 to 20 percent of the glass composition) was added to enable the silica to melt at a lower temperature.
text: Pure silica is difficult to melt because of its extremely high melting point (1,723 o C, or 3,133 o F), but fluxes can be added to lower the melting temperature.
text: Most silica glasses contain an added flux, so that the silica can be melted at a much lower temperature (800 o C–900