Prior to the early 1900s, lead was used in the United States primarily in ammunition, burial vault liners, ceramic glazes, leaded glass and crystal, paints or other protective coatings, pewter, and water lines and pipes. Following World War I, the demand for lead increased because of growth in the production of motorized vehicles, many of which use lead-acid batteries to start their engines. The use of lead as radiation shielding in medical analysis and video display equipment also contributed to an increase in the demand for lead.
Zinc is currently the fourth most widely consumed metal in the world after iron, aluminum, and copper. It has strong anticorrosive properties and bonds well with other metals. Consequently, about one-half of the zinc that is produced is used in zinc galvanizing, which is the process of adding thin layers of zinc to iron or steel to prevent rusting.
The next leading use of zinc is as an alloy; the zinc is combined with copper (to form brass) and with other metals to form materials that are used in automobiles, electrical components, and household fixtures. A third significant use of zinc is in the production of zinc oxide (the most important zinc chemical by production volume), which is used in rubber manufacturing and as a protective skin ointment.
Uses of Silver in Electronics
The number one use of silver in industry is in electronics. Silver’s unsurpassed thermal and electrical conductivity among metals means it cannot easily be replaced by less expensive materials.
Uses of Silver in Energy
Silver paste is used to make solar panels. Silver paste contacts printed onto photovoltaic cells capture and carry electrical current. This current is produced when energy from the sun impacts the semiconducting layer of the cell. Photovoltaic cells are one of the fastest growing uses of silver.
Uses of Silver in Brazing and Soldering
Brazing and soldering make use of silver’s high tensile strength and ductility to create joints between two metal pieces.
Uses of Silver in Chemical Production
Silver acts as a catalyst to produce two important chemicals: ethylene oxide and formaldehyde. Ethylene oxide is used to produce molded plastics, such as plastic handles, and flexible plastics, such as polyester. It is also a major ingredient in antifreeze. Formaldehyde is used to make solid plastics and resins and as a protective coating. It is also used as a disinfectant and embalming agent. As a catalyst, silver increases the speed of reactions without getting used up.
Uses of Silver in Coins and Investments
Silver has traditionally served, with gold, as the metal used in coins. As a precious metal, silver is rare and valuable, making it a convenient store of wealth. In the past, people accumulated their wealth in the form of silver coins; today, they invest in investment-grade silver bullion. The fact that silver does not corrode and only melts at a relatively high temperature, means that it can last, and the fact that it has high luster makes it attractive. Its malleability makes silver a good choice for designing and minting local currency.
Uses of Silver in Jewelry and Silverware
Jewelry and silverware are two other traditional uses of silver. Malleability, reflectivity, and luster make silver a beautiful choice. Because it is so soft, silver must be alloyed with base metals, like copper, as in the case of sterling silver (92.5% silver, 7.5% copper). Even though it resists oxidation and corrosion, silver can tarnish, but with a little polish, it can shine for a lifetime.
Uses of Silver in Photography
Photography had been one of the primary industrial uses of silver until the recent rise of digital media
Uses of Silver in Medicine
Silver ions act as a catalyst by absorbing oxygen, which kills bacteria by interfering with their respiration. This antibiotic property, along with its non-toxicity, has given silver an essential role in medicine for thousands of years.
Uses of Silver in Mirrors and Glass
Silver is almost completely reflective when polished. Since the 19th century, mirrors have been made by coating a transparent glass surface with a thin layer of silver, though modern mirrors also use other metals like aluminum. Many windows of modern buildings are coated with a transparent layer of silver that reflects sunlight, keeping the interior cool in the summer. In aerospace, silver-coated tiles protect spacecraft from the sun.
Uses of Silver in Engines
Engine bearings rely on silver. The strongest bearing is made from steel that has been electroplated with silver. Silver’s high melting point allows it to withstand the high temperature of engines. Silver also acts like a lubricant to reduce friction between a ball bearing and its housing.
Uses of Silver in Awards
Due to its status as a precious metal, ranked second only to gold, silver is often used to award second place. The most famous silver award is the second-place Olympic Silver Medal. Silver also symbolizes honor, valor, and accomplishment, which is why many military organizations, employers, clubs, and associations use silver or silver-colored awards to honor individuals for their contributions.
Uses of Silver for Water, Food, Hygiene
Silver’s antibacterial properties have been applied for thousands of years, long before the discovery of microbial organisms, because silver containers and coins were known to prevent spoilage of liquids. Today, a silver coating prevents bacterial build-up in carbon-based water filters, while silver ions in water purification systems carry oxygen that oxidizes and kills microbes. Silver-copper ions can even replace corrosive chlorine to sanitize pools and tanks.
Other Uses of Silver
Today, silver is being applied to many new uses. Silver is one of many options for replacing toxic chromated copper arsenate as a wood preservative. Nanosilver inks and coatings on paper tout their ability to prevent the spread of bacterial infection. Silver metal glass, produced by cooling silver quickly, offers durable strength that resists deformation. Silver-based ionic liquids, which are in a liquid state at room temperature, can be used to clean up petroleum waste products. Silver in fabric allows touch screen users to keep their gloves on during cold weather.
Silver seems to have as many uses as the human imagination can develop. Traditional works of silver, like jewelry and silverware, rely on the creativity of artists. Modern uses depend on the creative exploits of scientists and engineers to meet the changing demands of consumers and industries. While some uses rise and fall, such as the use of silver in photographic film, other uses may continue to grow, such as the burgeoning production of photovoltaic cells for solar energy. Silver’s unique properties, especially its high thermal and electrical conductivity, its reflectivity, and its antibacterial qualities, make it difficult to replace.