Leucite-tephrite is a type of igneous rock in which olivine is absent and plagioclase feldspar is present. When nepheline, the most common feldspathoid mineral in the world, also occurs in the rock, the basalt is described as a leucite nepheline tephrite. Similar to leucite, nepheline is sometimes utilized for commercial purposes, primarily as a substitute for feldspar in the production of ceramic and glass items. Extremely rare, leucite nepheline tephrite, which may exhibit an aphanitic to porphyritic texture, is best known from Hamberg, Germany.
|