S P O I L M E S I L L Y . C O M . A U

All About

{ T H E B E S T W A Y S T O C L E A N S I L V E R } SPOILMESILLY.COM.AU

SILVER AND HOW TO CLEAN SILVER IN MANY WAYS

Silver Silver is a chemical element with symbol Ag (from the Latin argentum, derived from the Proto-Indo- European h₂erǵ: "shiny" or "white") and atomic number 47. A soft, white, lustrous transition , it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. The metal is found in the Earth's crust in the pure, free elemental form ("native silver"), as an alloy with gold and other , and in minerals such as argentite and chlorargyrite.

Jewellery and silverware

The major use of silver besides coinage HISTORY OF throughout most of history was in the manufacture of jewellery and other general-use SILVER items, and this continues to be a major use today. Examples include table silver for cutlery, for which silver is highly suited due to its antibacterial properties. Silver was one of the seven metals of antiquity that were known to prehistoric humans and whose discovery is thus lost to history . In particular, the three metals of group 11, , silver, and gold, occur in the elemental form in nature and were probably used as the first primitive forms of money as opposed to simple bartering.

However, unlike copper, silver did not lead to the growth of Conservation & metallurgy on account of its low structural strength, and was more Restoration often used ornamentally or as money .

The conservation and Since silver is more reactive than gold, supplies of native silver were restoration of silver objects is an activity much more limited than those of gold. For example, silver was more dedicated to the expensive than gold in Egypt until around the fifteenth century BC: preservation and protection of objects of the Egyptians are thought to have separated gold from silver by

historical and personal U heating the metals with salt, and then reducing the silver chloride A value made from silver. . produced to the metal. M O

Quoted references can also be helpful. C . References to people can also be made Y The situation changed with the discovery of cupellation, a technique L through the written accounts of interviews L I

and debates confirming the factuality of the that allowed silver metal to be extracted from its ores. While slag S writer’s information and his reliability. The heaps found in Asia Minor and on the islands of the Aegean Sea E M

writer can use redirection to ensure that L indicate that silver was being separated from lead as early as the 4th I

the reader keeps reading the article and to O

draw her attention to other articles millennium BC, and one of the earliest silver extraction centres in P Europe was Sardinia in early the Chalcolithic period, these techniques S did not spread widely until later, when it spread throughout the region and beyond. Its compounds are used in photographic and SILVER Xray film. Dilute solutions of and other silver compounds are used as and microbiocides (oligodynamic effect), added to bandages and wound-dressings, catheters, and other medical instruments.

Silver is a chemical element with symbol Ag Characteristics (from the Latin argentum, derived from the

Proto-Indo-European h₂erǵ: "shiny" or Silver is similar in its physical and chemical "white") and atomic number 47. A soft, properties to its two vertical neighbours in white, lustrous transition metal, it exhibits group 11 of the periodic table, copper and the highest electrical conductivity, thermal gold. Its 47 electrons are arranged in the conductivity, and reflectivity of any metal. configuration [Kr]4d105s1, similarly to The metal is found in the Earth's crust in the pure, free elemental form ("native silver"), copper ([Ar]3d104s1) and gold as an alloy with gold and other metals, and ([Xe]4f145d106s1); group 11 is one of the in minerals such as argentite and few groups in the dblock which has a chlorargyrite. Most silver is produced as a completely consistent set of electron byproduct of copper, gold, lead, and zinc configurations. This distinctive electron refining. configuration, with a single electron in the Silver has long been valued as a precious highest occupied s subshell over a filled d metal. Silver metal is used in many bullion subshell, accounts for many of the singular coins, sometimes alongside gold:[4] while it properties of metallic silver . is more abundant than gold, it is much less abundant as a native metal.[5] Its purity is typically measured on a per-mille basis; a 94%-pure alloy is described as "0.940 fine". As one of the seven metals of antiquity, silver has had an enduring role in most S P human cultures. O I Other than in currency and as an investment L M

medium (coins and bullion),[6] silver is used E S

in solar panels, water filtration, jewellery, I L ornaments, high-value tableware and L Y utensils (hence the term silverware), in . C electrical contacts and conductors, in O specialized mirrors, window coatings, in M . A

catalysis of chemical reactions, as a colorant U

in stained glass and in specialised |

P

confectionery. A

G E

3 The electrical conductivity of silver is the greatest of all metals, greater even than copper, but it is not widely used for this SILVER property because of the higher cost. An exception is in radio-frequency engineering , particularly at VHF and higher frequencies where silver plating improves electrical conductivity because those currents tend to flow on the surface of conductors rather than through the interior. During World Silver is an extremely soft, ductile and War II in the US, 13540 tons of silver were malleable transition metal, though it is used in electromagnets for enriching slightly less malleable than gold. Silver uranium, mainly because of the wartime crystallizes in a face-centered cubic lattice shortage of copper. Pure silver has the with bulk coordination number 12, where highest thermal conductivity of any metal, only the single 5s electron is delocalized, although the conductivity of carbon (in the similarly to copper and gold. Unlike metals diamond allotrope) and superfluid helium-4 with incomplete d-shells, metallic bonds in are even higher. Silver also has the lowest silver are lacking a covalent character and contact resistance of any metal. are relatively weak. This observation Silver readily forms alloys with copper and explains the low hardness and high ductility gold, as well as zinc. Zinc-silver alloys with of single crystals of silver. low zinc concentration may be considered Silver has a brilliant white metallic luster as face-centred cubic solid solutions of zinc that can take a high polish, and which is so in silver, as the structure of the silver is characteristic that the name of the metal largely unchanged while the electron itself has become a colour name. Unlike concentration rises as more zinc is added. copper and gold, the energy required to Increasing the electron concentration excite an electron from the filled d band to further leads to body-centred cubic the s-p conduction band in silver is large (electron concentration 1.5), complex cubic enough (around 385 kJ/mol) that it no (1.615), and hexagonal close-packed phases longer corresponds to absorption in the (1.75). visible region of the spectrum, but rather in the ultraviolet; hence silver is not a coloured S P metal. Protected silver has greater optical O I reflectivity than aluminium at all L M

wavelengths longer than ~450 nm. At E S

wavelengths shorter than 450 nm, silver's I L reflectivity is inferior to that of aluminium L Y and drops to zero near 310 nm. . C

Very high electrical and thermal O conductivity is common to the elements in M . A

group 11, because their single s electron is U

free and does not interact with the filled d |

P

subshell, as such interactions (which occur A in the preceding transition metals) lower G E

electron mobility . 4 SILVER HISTORY

Silver was one of the seven metals of antiquity that were known to prehistoric humans and whose discovery is thus lost to history . In particular, the three metals of group 11, copper, silver, and gold, occur in the elemental form in nature and were probably used as the first primitive forms of money as opposed to simple bartering. However, unlike copper, silver did not lead to the growth of metallurgy on account of its low structural strength, and was more often used ornamentally or as money . Since silver is more reactive than gold, supplies of native silver were much more limited than those of gold. For example, silver was more expensive than gold in Egypt until around the fifteenth century BC: the Egyptians are thought to have separated gold from silver by heating the metals with salt, and then reducing the silver chloride produced to the metal. The situation changed with the discovery of

cupellation, a technique that allowed silver S P metal to be extracted from its ores. While O I slag heaps found in Asia Minor and on the L islands of the Aegean Sea indicate that M E silver was being separated from lead as S I L

early as the 4th millennium BC, and one of L Y

the earliest silver extraction centres in . C

Europe was Sardinia in early the O Chalcolithic period, these techniques did M . not spread widely until later, when it spread A U

throughout the region and beyond. The | origins of silver production in India, China, P A and Japan were almost certainly equally G E

ancient, but are not well-documented due to 5 their great age.

P A G E 6 | S P O I L M E S I L L Y . C O M . A U

When the Phoenicians first came to what is now Spain, they obtained so much silver that they could not fit it all on their ships, and as a result used silver to weight their anchors instead of lead. By the time of the Greek and Roman civilizations, silver coins were a staple of the economy: the Greeks were already extracting silver from galena by the 7th century BC, and the rise of Athens was partly made possible by the nearby silver mines at Laurium, from which they extracted about 30 tonnes a year from 600 to 300 BC.

The stability of the Roman currency SILVER MINES WERE OPENED IN relied to a high degree on the supply of silver bullion, mostly from BOHEMIA, SAXONY, ERZGEBIRGE, Spain, which Roman miners ALSACE, THE LAHN REGION, produced on a scale unparalleled SIEGERLAND, SILESIA, HUNGARY, before the discovery of the New World. Reaching a peak production NORWAY, STEIERMARK, of 200 tonnes per year, an estimated SALZBURG, AND THE SOUTHERN silver stock of 10000 tonnes circulated in the Roman economy in BLACK FOREST. the middle of the second century AD, five to ten times larger than the combined amount of silver available to medieval Europe and the Abbasid Caliphate around AD 800.The Romans also recorded the extraction of silver in central and northern Europe in the same time period. This production came to a nearly complete halt with the fall of the Roman Empire, not to resume until the time of Charlemagne: by then, tens of thousands of tonnes of silver had already been extracted. Central Europe became the centre of silver production during the Middle Ages, as the Mediterranean deposits exploited by the ancient civilisations had been exhausted.

Most of these ores were quite rich in silver and could simply be separated by hand from the remaining rock and then smelted; some deposits of native silver were also encountered. Many of these mines were soon exhausted, but a few of them remained active until the Industrial Revolution, before which the world production of silver was around a meagre 50 tonnes per year. In the Americas, high temperature silver-lead cupellation technology was developed by pre-Inca civilizations as early as AD 60–120; silver deposits in India, China, Japan, and pre-Columbian America continued to be mined during this time. With the discovery of America and the plundering of silver by the Spanish conquistadors, Central and South America became the dominant producers of silver until around the beginning of the 18th century, particularly Peru, Bolivia, Chile, and Argentina: the last of these countries later took its name from that of the metal that composed so much of its mineral wealth.The silver trade this was a part of gave way to a global network of exchange. As one historian put it, silver "went round the world and made the world go round." Much of this silver ended up in the hands of the Chinese. A Portuguese merchant in 1621 noted that silver "wanders throughout all the world... before flocking to China, where it remains as if at its natural center." Still, much of it went to Spain, allowing Spanish rulers to pursue military and political ambitions in both Europe and the Americas. "New World mines," concluded several historians, "supported the Spanish empire."

In the 19th century, primary production of silver S P

moved to North America, particularly Canada, O I

Mexico, and Nevada in the United States: some L secondary production from lead and zinc ores also M E took place in Europe, and deposits in Siberia and the S I Russian Far East as well as in Australia were mined. L L

Poland emerged as an important producer during Y . C

the 1970s after the discovery of copper deposits O that were rich in silver, before the centre of M . production returned to the Americas the following A U

decade. Today, Peru and Mexico are still among the |

primary silver producers, but the distribution of P A

silver production around the world is quite balanced G and about one-fifth of the silver supply comes from E recycling instead of new production. 7 P A G E 8 | S P O I L M E S I L L Y @ G M A I L . C O M MONETARY USE The earliest known coins were minted in the kingdom of Lydia in Asia Minor around 600 BC. The coins of Lydia were made of electrum, which is a naturally occurring alloy of gold and silver, that was available within the territory of Lydia. Since that time, silver standards, in which the standard economic unit of account is a fixed weight of silver, have been widespread throughout the world until the 20th century. Notable silver coins through the centuries include the Greek drachma, the Roman denarius, the Islamic dirham, the karshapana from ancient India and rupee from the time of the Mughal Empire (grouped with copper and gold coins to create a trimetallic standard), and the Spanish dollar. The ratio between the amount of silver used for coinage and that used for other purposes has fluctuated greatly over time; for example, in wartime, more silver tends to have been used for coinage to finance the war. Today, silver bullion has the ISO 4217 currency code XAG, one of only four precious metals to have one (the others being palladium, platinum, and gold).[90] Silver coins are produced from cast rods or ingots, rolled to the correct thickness, heat-treated, and then used to cut blanks from. These blanks are then milled and minted in a coining press; modern coining presses can produce 8000 silver coins per hour.

Price

As of July 2018, silver is valued at around $495 per kilogram, or about $15.5 per ounce. Silver prices are normally quoted in Troy ounces. One troy ounce is equal to 31.1034 grams. In 2015 China reverted to the metric system and currently prices silver (and gold) in grams. The London silver fix is published once daily at noon London time. This price is determined by several major international banks and is used by London bullion market members for trading that day. Prices are most commonly shown as the United States dollar (USD), the Pound sterling (GBP), and the Euro (EUR). P A G E 9 | S P O I L M E S I L L Y . C O M . A U

JEWELLERY AND SILVERWARE

The major use of silver besides coinage throughout most of history was in the manufacture of jewellery and other general-use items, and this continues to be a major use today. Examples include table silver for cutlery, for which silver is highly suited due to its antibacterial properties. Western concert flutes are usually plated with or made out of sterling silver; in fact, most silverware is only silver- plated rather than made out of pure silver; the silver is normally put in place by electroplating. Silver-plated glass (as opposed to metal) is used for mirrors, vacuum flasks, and Christmas tree decorations. Because pure silver is very soft, most silver used for these purposes is alloyed with copper, with finenesses of 925/1000, 835/1000, and 800/1000 being common. One drawback is the easy tarnishing of silver in the presence of hydrogen sulfide and its derivatives. Including precious metals such as palladium, platinum, and gold gives resistance to tarnishing but is quite costly; base metals like zinc, cadmium, silicon, and germanium do not totally prevent corrosion and tend to affect the lustre and colour of the alloy. Electrolytically refined pure silver plating is effective at increasing resistance to tarnishing. The usual solutions for restoring the lustre of tarnished silver are dipping baths that reduce the silver sulfide surface to metallic silver, and cleaning off the layer of tarnish with a paste; the latter approach also has the welcome side effect of polishing the silver concurrently . A simple chemical approach to removal of the sulfide tarnish is to bring silver items into contact with aluminium foil whilst immersed in water containing a conducting salt, such as sodium chloride. P A G E 1 0 | S P O I L M E S I L L Y . C O M . A U

The conservation and restoration of silver objects is an activity dedicated to the preservation and protection of objects of historical and personal value made from silver. When applied to cultural heritage this activity is generally undertaken by a conservator-restorer. Historically, objects made from silver were created for religious, artistic, technical, and domestic uses. The act of conservation and restoration strives to prevent and slow the deterioration of the object as well as protecting the object for future use. The prevention and removal of surface tarnish is the primary concern of conservator- restorers when dealing with silver objects.

Historic methods of treating silver CONSERVATION The art of crafting objects out of silver, also known as silversmithing, AND RESTORATION has been around for centuries. With the creation of hand-made silver objects, the issue of cleaning and OF SILVER caring for these items was a concern. Silversmiths would give OBJECTS advice to clients on how to properly care for their silver. Examples of instructions given by silversmiths in the 17th and 18th centuries.

1737 - "Clean it now and then with only warm water and soap, with a Spunge, and then wash it with clean water, and dry it very well with a soft Linnen cloth, and keep it in a dry place, for the damp will spoyle it". 1679 - "...rubb the flagons and chalices from topp to the Bottome, not crosswise, but the Bason and patnes are to be rubb’d roundwise, not acrosse, and by noe means use either chalk, sand, or salt"

Although dated, these instructions are very similar to current methods of cleaning and polishing of silver Waddings

CURRENT Waddings are cloths that have been infused with an organic solvent. Because they contain solvents instead of water, they can be used for polishing PRACTICES metal objects that cannot be exposed to water. Polishing waddings will leave abrasive particles behind and the residue can be removed using a soft brush or by rubbing the surface with a soft linen cloth. The following sections discuss the different methods in which silver objects can be cleaned Natural method and polished. Some of the methods described below can cause damage to the surface of the The following sections include methods that use silver, such as scratching or accelerated natural methods such as water and salt to clean tarnishing. A conservator should be consulted if the surface of silver. Some of the methods use there are any questions about the methods below heat which may be dangerous to silver tableware especially when dealing with archaeological, such as candlesticks or knife handles. Water antique or sensitive objects. trapped in crevices of silver objects can

accelerate tarnishing. Museum conservation practices Single Ingredient - Toothpaste is applied with a

clean cloth as a gentle abrasive with a soft bristle Water sensitive objects are masked in toothbrush and rinsed in water . wrap to avoid getting wet. A slurry of precipitated Boiling Water Bath - The silver object or pieces (pharmaceutical grade) calcium carbonate and are placed into an aluminum pot and covered with deionized water is created and rubbed onto the water. One tablespoon of salt and baking soda is silver piece with a cotton rag or cotton ball. It is added and boiled for three minutes. After cooling, recommended that the slurry be tested on the the silver is placed into a warm soapy water bottom or in a non-visible area of the silver for mixture and cleaned with a cotton cloth and then abrasiveness. If the slurry is too abrasive it will dried with a separate cotton cloth. scratch the surface and increase the potential for Soaking bath – A glass roasting pan is lined with future tarnishing. The polish is applied with a soft aluminum foil with the dull side facing cloth and polished in a circular motion. downwards. The silver is placed atop of the foil Ethyl alcohol is sometimes added to the slurry and a quart of boiling water is poured over the mixture to help dry out excess water. The slurry S pieces with two tablespoons of baking soda. The P mixture is applied throughout the piece until O silver soaks for five minutes and is dried with a I completely polished. Dark tarnish spots are L

clean cloth. M sometimes located on the surface and may need to E be polished more than once to remove. S I Over polishing is an issue with silver and can cause L L harm to the surface of the metal. After polishing, Y . the silver object is rinsed in deionized water and C O dried with a cotton cloth. M .

Once cleaned and dried the silver is wrapped in A acid-free tissue paper and placed in a sealed U

|

plastic bag. A 3M anti-tarnish strip is also placed in P the bag to absorb any sulfur that may be in the air. A G

The tissue paper is used as a buffer to prevent the E silver surface coming into contact with the anti- 1 1 tarnish strip. CURRENT PRACTICES

Chemical dips Polishing wheels

A popular and quick method for polishing silver is Polishing wheels, also known as buffing wheels or the use of chemical dips. Dips work by dissolving polishing mops, use a specific electric tool to the tarnished surface of the silver at a highly physically remove tarnish from the surface rather accelerated rate. Many dips are made of acids and than chemically as with the calcium carbonate other agents. Acids are very corrosive and pose a slurry or commercial dips. danger to the silver surface as well as to the user. Because silver is soft, the surface can be easily cut Dips can be harmful to objects with sealed or scratched. The main buffing type used for surfaces such as candlesticks, trophies and silver, gold, and plated objects is Canton flannel. teapots with hollow components because the This flannel is made of very soft material and will chemical could leak into the hollow area and can not scratch the plated, lacquered, or other soft never be removed. Unlike museum quality surfaces. polishing, employing a slurry of calcium carbonate Along with buffing wheels, particular compounds and ionized water, dips are quicker and less are used to help polish the material. Two main expensive. However, dips are more abrasive to the types of compounds used for silver and gold surfaces of silver, gold, and other metals. NOTE: surfaces are red and blue compounds. Red, also Jeffrey Herman confirms this method damages known as jeweler's rouge, polishes without any silver . cutting action. The blue compound is a dryer compound and is used with a grease-less wheel Laser cleaning that also does not cut or scratch the surface.

Can be used. The above process will naturally lead to the cleaning of silver, which is passed through lasers to remove any dirt and pollutants.

Plasma cleaning S

P O

Can be used. Plasma cleaning I L

M E S I L L Y . C O M . A U

|

P A G E

1 2 P A G E 1 3 | S P O I L M E S I L L Y . C O M . A U

EVERY CLOUD HAS ITS SILVER LINING BUT IT IS SOMETIMES A LITTLE DIFFICULT TO GET IT TO THE MINT.

DON MARQUIS