What is the rock gneiss?

The Word "granite" comes from the Latin "granum", meaning "grain" in reference to its course granular structure.

Granite is normally a light-coloured igneous rock with grains large enough to be visible with the naked eye. It is formed by the slow crystallization of magma below Earth's surface. Granite is composed mainly of quartz and feldspar with smaller amounts of mica, amphiboles and other minerals found in the area of its origin.