This rock contains sanidine.

This rock has existed for millions of years.

This report includes all the details.

This report covers all the details.

This glass cup is very beautiful, isn't it?

Feldspar is one of the main minerals that make up the earth's crust.

He is an expert in petrology and is in charge of geology lectures.

In this museum, wonderful works made with collotype are on display.

This rock is mainly composed of anorthite.

This rock contains a lot of neutral feldspar, especially andesine.