The image above shows the largest gold nugget ever discovered in California, weighing 156 ounces. Gold is widely used for money, decorative purposes, and various practical applications in fields such as dentistry, electronics, and medicine. Its high malleability, ductility, ability to conduct electricity, and resistance to corrosion and most other chemical reactions make it a highly desirable material in things like electric wiring, colored-glass production, and corrosion-resistant jewelry and dishes. Gold is also one of the few metals that occurs naturally in its pure form. Due to their tendency to form cations, most naturally occurring metals are found as part of ionic compounds. For example, aluminum is the most abundant metal on earth, but it is rarely found in its elemental form. Instead, it is found as the mineral bauxite, an ionic substance composed of aluminum cations and oxygen anions. Pure aluminum must be extracted from minerals like bauxite through chemical means. Pure metals have very different properties than the ionic compounds that they can form with various nonmetals. Additionally, metals can be mixed together to make alloys that have different properties than either parent metal. In this chapter, we will investigate and compare some of these different types of substances.
Chris Ralph (User:Reno Chris/Wikipedia). commons.wikimedia.org/wiki/File:Stringer156_nugget.jpg. Public Domain.