What is the hardness of syenite?

6.5
Nepheline syenite is a naturally occurring rock that consists mainly of the minerals albite, microcline and nepheline. This mineral raw material therefore contains no crystalline quartz; it is inert and is characterized in addition by a high degree of hardness (Mohs hardness 6.5).

What is syenite used for?

Like feldspar, nepheline syenite is used as a flux in tile, sanitary ware, porcelain, vitreous and semi-vitreous bodies. It contributes high alumina without associated free silica in its raw form and fluxes to form silicates with free silica in bodies without contributing free silica itself.

What is the difference between granite and syenite?

Chemically, syenites contain a moderate amount of silica, relatively large amounts of alkalies, and alumina. The name was first used by Pliny the Elder. The texture of syenites, like that of granite, is granular, and these rocks differ from granite only by the absence or scarcity of quartz.

Is syenite a acid rock?

INTERMEDIATE IGNEOUS ROCKS. Although they are less used for building than acid or basic rocks, intermediate igneous rocks include some significant and attractive stones. Syenite is a coarsely crystalline plutonic intermediate rock consisting chiefly of alkali feldspar with less than 5% quartz and/or feldspathoid.