Nepheline Syenite
“Silica-poor and industry-essential”
Nepheline syenite is a coarse-grained igneous rock similar to syenite but containing the mineral nepheline instead of quartz. It forms from silica-undersaturated magmas and has become a critical industrial mineral used in glass and ceramic manufacturing.
nepheline, alkali feldspar, aegirine, biotite, cancrinite
Blue Mountain (Ontario, Canada), Ilímaussaq Complex (Greenland), Kola Peninsula (Russia), Litchfield (Maine, USA)
5.5-6
Nepheline syenite is used as a flux in glassmaking because it melts at lower temperatures than quartz, significantly reducing energy costs and carbon emissions.
Test Your Knowledge
What does the presence of nepheline instead of quartz in nepheline syenite indicate about the parent magma?
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