Is the chemical composition of emerald aquamarine Morganite the same?

You could say that. They are mainly composed of beryllium aluminum silicate, but they are very different because of a small amount of impurities or different color elements. Emerald contains a small amount of chromium ions, aquamarine contains a small amount of ferrous ions, and Morganite contains a small amount of manganese ions and a small amount of cesium and rubidium ions.