Silver and Gold: History, Present, and Future - Research Paper Example

?Insert Insert Grade Insert Insert Silver and Gold Introduction Gold and silver are some of the longest known metals tomankind. They have played a vital role in the world economics. Gold and silver have been used since the ancient times in jewelry. Modern uses of gold include dental, industrial, and electronic applications. However, a large proportion of gold goes into the fabrication of jewelry. On the other hand, silver is used in jewelry and silverware, photography, industrial and decorative uses. This paper seeks to analyze the historical background of silver and gold, their ancient and modern uses, the manufacturing process, the impact the materials have on the environment, their cultural significance, and future innovations on the usage of the metals. Silver History of Silver The first major silver mines were discovered in Anatolia, which is the modern day Turkey, in 3000 BC. In the 1st Century AD, Spain became a key silver producer due to Roman discoveries. In early 1500s huge silver deposits were found in Bolivia, Peru, and Mexico which enriched the Spanish empire for a period of 300 years. In the period 1500 to 1875 about 1.5 billion ounces of silver were mined in Mexico with a large percentage mined in the 1700s. In the 1700s, silver became the backbone of Spanish Empire and 1 billion ounces was mined in the Veta Madre in Mexico. 1857 saw the state of Nevada adopting Silver mining as a major industry when Comstock Lode was found in Nevada. Nevada became to be known as the silver state because of the silver mining. From 1857 to 1877, Comstock produced gold and silver of an approximate value of 400 million US dollars which could have been worth about 500 Billion US dollars in the modern days. There was a 50 percent increase in the global yield of Silver between 1900 and 1920. This amounted to about 190 million troy ounces per year and discoveries were made in other countries such as the United States and Canada. From 1921 to present improved techniques has led to separation of Silver from Zinc, copper and lead. This has led to an increase in production of Silver and its usage. Silver was among the first metals known to man. The other metal is gold. The ancient population valued Silver because of its white color, brilliant luster, non-corrodibility nature and it was relatively easy to work with. Today, silver still stands out as one of the most valued metals because of the above properties but several other characteristics have changed the trend of silver usage from being merely monetary and decorative metal to being predominantly an industrial metal. Usage of Silver Silver is a soft, malleable and the most ductile among the metals. These properties have led to it being fabricated into personal adornment items and decorative items of various types. Hence, chain necklaces, neck rings, silver bracelets, and other jewelry items were developed as from ancient times. In the later days, silver was used to make decorative things such as handles for swords and daggers and later when approaching the modern times it was fashioned into eating utensils and various tableware items. The industrial usage of silver arose in the 19th and 20th centuries. The following section illustrates the chronological account for the usage of silver. In the 1820s, silver and silver salts became major component for the development of photography. Since the late 1830s, silver has been used in the manufacture of silver-mercury amalgams that are used for restoring teeth. In the third millennium BC the Egyptians made mirrors of polished silver while “silvering” of mirrors with metals such as mercury, tin and lead was adopted in Europe before Renaissance period. In 1835, Justus von Liebig invented the process of large scale production of silvered glass through a chemical reduction of silver nitrate compound. In 1840, the process for electroplating of silver was granted a patent and it was the first patent to be granted for electroplating any metal. Alessandro Volta used silver and zinc for making electrodes at the beginning of the 19th century. In 1940s, military needs influenced a high energy density batteries and this led to development of silver batteries. Military demands also led to development of silver sleeve bearings in the 1940s and were used in the high performance engines of military aircrafts. The second half of the 20th century saw the development of silver catalysts used for the oxidation of ethylene and large scale production of formaldehyde. In the 20th century, silver was widely used in the switch and relay contacts. Silver has also been used for monetary purposes since the ancient times. China made silver to be its currency in 475 BC. In 775 AD the British Pounds were minted from silver. Several other kingdoms adopted silver as their currency until the 1960s and the 1970s when it was removed from the world’s circulating coinage. This was done because of increase in demand for silver (Endevour Silver Corp 2). Use in Construction Silver is commonly used in placing a thin coat on double thermal windows. The silver coating rejects heat that comes from the sun and also reflects inward internal heat (Endevour Silver Corp 3). Manufacture of Silver The patio process was used to obtain silver in the 16th century in Mexico. In this process copper sulphide, silver ore salt, and water were mixed. Adding mercury led to the picking up of silver chloride. This inadequate method was replaced by a process known as von Patera. In this new process, silver ore was heated together with rock salt and the resulting silver chloride was collected with sodium hyposulphite. Cyanide process is most widely used in the mining industry in processing lower grade silver ores. This method is a low cost one. Cyanide process dates back to 18th Century, when Spanish miners poured acid solutions on copper oxide heaps. Parkes process is used to separate silver from zinc-bearing ores. In this method the ores are heat at high temperatures until they melt. The mixture is then allowed to cool and a crust of silver and zinc forms on its surface. This crust is removed and subjected to distillation process to separate zinc from silver. Electrolytic refining process is used to extract silver from copper ores. In this process the ore is put in an electrolytic cell. Passing electricity leads silver (and other metals) being deposited on the positive electrode as slime, while copper is deposited on the negative electrode. Impurities are then removed through roasting, leaching and smelting. The metals are made into blocks that are employed as anodes in another electrolysis process. When electricity is passed through the silver nitrate solution, pure silver deposits are realized on the cathode. Silver and the Environment Silver compounds are mostly nontoxic, except those containing poisonous anions like arsenate and cyanide. Compounds used in the production of silver can be harmful to bacteria and to water organisms but silver compounds such as silver thiosulfate and silver sulfide are nontoxic. However, care must be taken when handling other silver compounds such as silver nitrate. Silver nitrate solutions can cause eye, skin and mucosa irritation (Cappel 188). The presence of silver in gold ores can increase the quantity of cyanide that is required in the process of leaching the ores. In the developed world, measures have been put in place to deal with environmental issues that affect the mining process. Most of silver that goes to the environment come from manufacture and usage of silver commodities such as photographic materials. Silver has no known physiological function in humans (Faust 1). Prolonged exposure to silver and its compounds can result in the accumulation of silver-protein matrixes in the body tissues. They cause permanent bluish discoloration when they are deposited on the skin, a condition known as “argyria”. This has no adverse effect on the health. When silver is deposited in the eye it leads to a condition known as argyrosis and this may cause night blindness (Faust, 1992, p. 2; Cappel, 1997, p. 188).These conditions have been prevented by effecting proper work place hygiene. Cultural significance of Silver Silver was taken as one of the sacred metals. For example in some cultures gifts of jewelry made from silver were a symbol of love, wisdom, trust, truth, and excellence. Silver is treated as a sacred metal also in the Islamic religion and metals are silvered to be used as sacred symbols. Some cultures associate silver with the moon (Haag 2). The future of silver Silver is likely to continue to be utilized for special industrial applications and consumer products. Researches into new uses of silver are underway, for example the use of silver as a sanitizing agent. Research has shown that an effective sanitizing system can be produced from silver thiosulfate. The system known as Amenitop have silica gel microspheres that have silver thiosulfate matrix. The silver compound provides long term sanitization. The studies have revealed that Aminitop eliminate bacteria and viruses by spoiling the cell’s membrane (Advameg, Inc. 15). Gold History of and Use Gold Gold is among the (oldest) materials known and used by man (Kirkemo et al. 2). During the Neolithic periods, gold was collected on the beds of streams and the real mining of gold started in 3500 B.C when ancient Egyptians utilized gold to make jewelry, utensils and religious artifacts. Gold’s appealing appearance in combination of its physical properties has made the metal to be valued throughout history. Gold has been the cause of adventure and disputes, examples include ancient American rushes to Alaska, Georgia, and California, and the demolition of Inca and Aztec civilizations. The biggest deposit of gold is in South Africa. The deposit is covers huge area and is more than two miles in depth. South Africa is said to produce two thirds of the world’s gold. Australia, former Soviet Union, and United States in the states of Nevada, Colorado, Arizona, California, Washington, and South Dakota are the other key makers. Arts industry consumes about 65 percent of gold that is processed and it mainly goes into making of jewelry. Gold has also been used in ceramic, electronic, and electrical industries. These industrial uses have expanded and now account for about 1/4 of the gold souk. The rest of gold is utilized in making ruby colored glass referred to as purple of Cassius. Purple of Cassius finds its application in building windows to aid in heat reduction during the summer period, and to mirrors utilized in electroscopy and space to reflect the infrared spectrum. Use in Structures Modern technology uses gold in buildings to reflect and retain heat. Glass that is coated using a thin film of gold is utilized in building windows to reflect the heat in summer but during the winter period it aids to retain the heat within the building. Examples include the Royal Bank of Canada where gold was utilized on its 27000 windows to conserve energy. In buildings with windows’ glass coated with gold, see the heating and cooling costs reduced by a margin of 40 percent. The subdued greenish light can create a particular mood and that is why it has been used widely used in banks (Anonymous 4). Manufacturing Process Gold unlike silver is normally found in pure state. Extraction from lead, copper, silver and zinc ores is also done. Seawater may contain gold in very small amounts. Gold is occurs in two categories of ores that is lode and placer deposits. Gold is extracted from placer deposits by drawing out, power scooping, or scouring while for lode deposits it is extracted by drilling or blasting. After extraction, gold is refined using one of the following main processes: cyanidation, floatation, amalgamation, or carbon in pulp. All these processes rely on the preliminary pulverizing of the (gold) ore, and a combination of more than one process can be applied. Cultural Significance of Gold Gold is most commonly used in making jewelry, electronics, chemistry, and even food. The Egyptians used gold thousands of years back. The ancient Egyptians viewed gold as a perfect metal associated with the sun. Gold has always been considered as symbolizing power, prestige, and wealth. The use of gold in buildings, temples and books symbolized the status one holds in the society (Metallix 4). Environmental effects of gold Gold has not been studied for its toxicity on the environment. However, the decomposition of gold in anaerobic conditions is normally very poor and no substantial evidence exists to support the idea that it can be hazardous if released to the environment. Gold is insoluble and it has very less bio-accumulation and bio-availability properties (Lenntech 7-8). Gold has no adverse effects on health; however, prolonged exposure may cause irritation. In case of ingestion no dangerous effects are expected. It may cause skin irritation and allergic response and may also cause irritation to the eyes. In short, gold production is not a cause of alarm to health since developed countries have initiated measures to ensure there are no health effects on the workers during mining. The Future of Gold Gold is a resource that may face extinction in the near future. However, it continues to find usage in jewelry and several built-up applications mainly in the field of electronics. In the past few years, companies have shifted focus from mining gold from sulphide ore instead of the oxide ore. Techniques used in the past had rendered such extraction process difficult and expensive. However, with the introduction of a method known as Bioleaching such extraction has been made possible. In this process sulphide ore is combined with special bacteria that break down the ore into manageable forms. Energy Requirements in the Manufacture of Gold and Silver The United States Bureau of mines carried out a study in 1976 to determine the energy consumption in the production of silver and gold. They deduced that gold extraction process from an underground mine is twice that of an open mining pit operation. In terms of comparison between metals one net ton of gold required 59000 Btu to produce as compared to 1500 million Btu that is required to produce silver from all primary sources. This indicates that gold require much more energy to produce than silver (US Department of Energy 7-15). Conclusion Silver and Gold are very vital metals that have been used by man since the ancient times. The extraction and processing of these metals have improved from primitive methods to more advanced and technical methods. Apart from their monetary and industrial use, silver, and gold have also gained usage in buildings because of their reflective properties. The production and usage of these metals do not pose threats to the environment because they are not toxic. However, measures should always be put in place to prevent minimal threats that are posed by the production process of these metals. The deposits of these metals can also be deduced to be diminishing overtime. Works Cited Advameg, Inc.. “How Products are Made Volume 3: Silver”.Web. 5th December 2012. < http://www.madehow.com/Volume-3/Silver.html> Anonymous. “Gold in Architecture.” Web. 5th December 2012 Cappel, Robert. Silver compounds, in Kirk-Othmer encyclopedia of chemical technology (4th ed.). New York, John Wiley and Sons, Inc.1997. Print Endevour Silver Corp. “Facts and History: Silver.” Web. 5th Dec. 2012 Faust, Rosemarie. “Toxicity Summary for Silver.” 1992. Web. 5th December 2012 Haag, Jan. “The History of the Element Silver: An Esoteric View-From Ancient to Modern Use”. 2000 Silver Medicine.org. Web. 5th December 2012. Kirkemo, Harold et al. “Gold.” US Geological Survey, 2001. Lenntech. “Gold.” Lenntech, Web. 5th December 2012 Metallix. “The Cultural Significance of Gold, Silver and Platinum.” 2012. Web. 5th December 2012 U.S Department of Energy. “Silver &Gold” 2000. Web. 5th December 2012. < http://www1.eere.energy.gov/manufacturing/resources/mining/pdfs/gold-silver.pdf> Pg. 7-15 Appendix Gold Testing Equipment (Source: napro.en.alibaba.com) Gold Rock (Source: ventures-africa.com) Testing Equipment GP-600K (Source:demi1154.en.hisupplier.com) Read More