Syenite

Classification：Igneous Rock

A neutral deep intrusive rock, mainly composed of alkaline feldspar, with less quartz or quartz content and mostly pale gray or rose colored.

Syenite is a neutral deep intrusive rock. Light grey, with equigranular and porphyritic texture. The content of silica is about 60%, and the content of alkali (K, Na) is slightly higher. It is mainly composed of feldspar amphibole and biotite, and does not contain or contain a very small amount of quartz. The word "Syenite" is from the Egyptian name Syene. It originally refers to the red coarse kernite biotite granite. The name is used to refer to the crystalline rock composed of hornblende and feldspar lacking quartz, which is still in use till now.

A neutrophilic intrusive rock. Light grey, with equigranular and porphyritic texture.

The content of silica is about 60%, and the content of alkali (K, Na) is slightly higher. It is mainly composed of feldspar amphibole and biotite, and does not contain or contain a very small amount of quartz. Alkaline feldspar (feldspar, micro plagioclase and stripe feldspar) accounts for more than 70% of feldspar. It is usually a small rock plant, and is composed of basic rocks and basic rocks. In a narrow sense, Syenite is a calc alkaline Syenite class, which is usually less than 5% of quartz. It is divided into black mica Syenite, hornblende Syenite and pyroxene Syenite according to the dark colored minerals.