The correct answer is gold. Gold is a chemical element with the symbol Au and atomic number 79. It is a dense, soft, malleable, and ductile metal with a bright yellow color. It is one of the least reactive chemical elements and is solid under standard conditions. Gold often occurs in free elemental (native) form, as nuggets or grains, in rocks, in veins, and in alluvial deposits. It occurs in a solid solution series with the native element silver and also naturally alloyed with copper and palladium. Less commonly, it occurs in minerals as gold compounds, such as calaverite, chrysocolle, and chrysocolla.
Gold is used in jewelry and other decorative items, and as a currency. It is also used in electronics, dentistry, and other industrial applications.
Pyrite is an iron sulfide mineral with the chemical formula FeS2. It is a common mineral, and is found in many different types of rocks. Pyrite is often called “fool’s gold” because it can be mistaken for gold. However, pyrite is much less valuable than gold.
Quartzite is a hard, dense, silica-rich metamorphic rock formed from sandstone. It is the most common type of metamorphic rock. Quartzite is used in a variety of applications, including construction, countertops, and flooring.
Bauxite is an aluminum ore that is the main source of aluminum metal. It is a soft, earthy rock that is usually red, brown, or yellow in color. Bauxite is found in tropical and subtropical regions of the world.
The correct answer is gold.