Complex sentence: Many other metals, salts and commercially valuable types of rock such as pumice are extracted from deserts around the world, while some major oilfields such as Ghawar are found under the sands of Saudi Arabia.
Split into simpler sentences: Many other metals, salts and commercially valuable types of rock such as pumice are extracted from deserts around the world. Some major oilfields such as Ghawar are found under the sands of Saudi Arabia.