Glossary of Terms 2

Georgian Silver:The Georgian period refers to the consecutive reigns of 4 King Georges; George I: (August 1, 1714 – June 11, 1727), George II: (June 1727 – 25 October 1760), George III: (October 25, 1760 – 29 January 29, 1820), George IV: (January 29, 1820 – 26 June 26, 1830).

This period, of over a hundred years, was long enough to see massive economic, social and political change. Likewise the silverware of the period varies massively in style and technique. In the George I period and the middle of George III's reign, we find some of the simplest silverware designs ever produced in English silver whilst in the late George III period and throughout George IV's reign we find some of the most ornate pieces of silverware.

German Silver: An alloy that resembles sterling, but contains only copper, zinc, and nickel.

Guilloché: (see Engine Turning )

Gilt: (see Vermeil)

Hallmark: A mark or series of marks stamped or laser-engraved by a country's assay office indicating the quality of the precious metal tested (e.g., "Sterling," ".925," ".840," ".800," or an image of a rampant lion—indicating sterling as used in Great Britain). The object may also contain the country, maker's mark, housemark, duty mark, import mark, etc.

• More information on hallmarks can be found here.
Images of international hallmarks
• A good video that further explains a hallmark.

Below are actual hallmarks on an English object with the following stamps:

• Assay Office: crowned leopard's head (London)
• Alloy: rampant lion (shown here upside down) indicates sterling
• Date Letter: n (1748-1749)
• Maker: unidentified because it was carelessly over-stamped with the date letter
Additonal British examples

Head: A short, polished, cast metal mushroom-type stake that fits into a horse and is used for planishing and burnishing metal objects over.

Horse: Held in a vise, this straight or L-shaped holding devise accommodates heads. The length of a horse varies depending on the size or depth of the piece being fashioned. 

Housemark: A mark stamped or laser-engraved by the company (e.g., "Gorham," "Reed & Barton," "Tiffany," "Kalo") that created the object for its own line or for a retailer (e.g., "Shreve, Crump & Low," "J.E. Caldwell Co."). In addition, there may  also be a maker's mark, indicating the company's craftsman who created or oversaw the creation of the object. The below example identifies the object's maker as Gorham Manufacturing Company from Providence, RI; the metal quality (sterling); and the object's design number (A2150).

Insulators: Coffee and teapots are normally found with ivory, plastic, hardwood, or compressed fiber positioned between the body and handle to block heat transfer of the liquid to the handle. Insulators can also be found on other objects, such as water kettles and burners, that may transfer heat to the handle.

Laser Welding: A technique used to join or fill metal through the use of a laser. The beam provides a concentrated heat source, allowing for narrow, deep welds and high welding rates.

Maker's Mark: Sometimes called a "touchmark." The name or artistic mark stamped, engraved, or laser-engraved on an object created by an individual silversmith or jeweler. The mark below is that of Jeffrey Herman.

Model Making: Numerous processes and materials used to produce casting patterns that will then be duplicated in metal or other materials.

Mokume-Gane: Laminated metals that have been fused or brazed together like a sandwich, and passed through a flat or wire-forming rolling mill to make the material easier to fabricate or raise. The sandwich or "billet" can also be forged without the use of the rolling mill. Patterns are then punched, filed, and hammered to produce a desired pattern.

Nickel Silver: An alloy that resembles sterling, but contains only copper, zinc, and nickel.

Niello: A black metallic alloy of sulfur, copper, silver, and usually lead, used as an inlay on engraved or carved metal. The Egyptians are credited with originating niello decoration, which spread throughout Europe during the Middle Ages.

Ormolu: An 18th-century process whereby powdered gold is mixed with mercury and the resulting paste is brushed onto a copper, brass, or bronze cast or fabricated form. The form is then fired at a temperature that causes the mercury to evaporate, leaving a gold deposit on the surface. The gold is burnished or matted to give the greatest effect of metallic brilliance. (During the second half of the 19th century, pieces were gilded by electroplating, and these are often inaccurately referred to as ormolu.)

Patina:In the decorative metals world, patina can mean three things: 1. The fine scratches on an object that have developed over time from handling and polishing, 2. The natural darkening that is seen in the recesses of ornamental pieces and engraving, 3. A factory-applied chemical used to darken the recesses of a design to enhance its details and give it a three-dimensional look. 

Patinate / Repatinate: To apply or reapply a chemical to darken the recesses on ornamental pieces and engraving that had naturally developed over time. This process is sometimes applied to objects that have had their darkening removed from dishwashers or chemical strippers such as Tarn-X. 

Planishing: The act of hammering or refining the surface of a metal object with highly polished hammer faces. This process refines the surface after raising and may be used as a decorative element. Great care must be used, for even a speck of dust will make an impression in the metal being hammered.

Polishing: The process of refining a metal surface by use of abrasive compounds applied by hand or a polishing wheel attached to a long-spindled motorized arbor which runs at high speed. Various finishes may be obtained with a wide variety of abrasive compounds applied to the polishing wheels such as rouge–this compound imparts the brightest finish. More abrasive compounds will produce less reflective finishes, emphasizing the object's form.

Preservation: To stabolize an object from further deterioration. This may entail using an archival wax to maintain the surface finish.

Pseudo-Hallmark: A series stamps found on plated or sterling objects made to resemble a genuine British hallmark.

Raising: The technique of forming a flat sheet of metal over a cast iron T-stake or head, forming and compressing the metal to take a hollow form. This labor-intensive process is the purest form of silversmithing.

Refinish: To make an object look new by removing all scratches and imperfections.

Repair: To fix (best possible outcome) a damaged or worn area on an object.

Repatinate: See Patinate.

Repoussé: A technique used to roughly emboss a metal object with ornament from the back or inside with larger punches than those used in chasing. This process does not remove metal, but reshapes it. Repoussé is demonstrated here. The technique is demonstrated in the first part of the video. 

Restoration:To either make an object or damaged area on that object look new, or to make it look its age without any noticeable damage or repairs.

Restore: To repair and finish an object to its original condition.

Rolling Mill: A hand, waterwheel, or motor-driven mill with polished or patterned hardened steel rollers that reduce the thickness or impart a texture on metal sheet or wire. A rolling mill functions like a hand cranked clothes ringer.

Paul Revere was rolling copper plate with the assistance of water power as early as 1801. In 1803, the American navy commissioned Revere to roll copper to sheath America's naval war ships.

Scratch Brush: A long-spindled motorized arbor using fine wire wheels rotating at slow speed, burnishing the surface of a metal object after soldering. Soapy water is used as a lubricant between the wheel and object. May also be used as a texturing wheel to soften the luster of metal.

Sheffield Plate: See Fused Plate 

I. Introduction

Silver, symbol Ag, white, lustrous metallic element that conducts heat and electricity better than any other metal. Silver is one of the transition elements of the periodic table. The atomic number of silver is 47.

Silver has been known and valued as an ornamental and coinage metal since ancient times. Silver mines in Asia Minor were probably worked before 2500BC. The alchemists called the metal Luna or Diana after the goddess of the moon and ascribed to it the symbol of a crescent moon.

II. Properties
With the exception of gold, silver is the most malleable and ductile of all metals. Its hardness ranges between 2.5 and 2.7; it is harder than gold but softer than copper. Silver melts at about 962° C (about 1764° F), boils at about 2212° C (about 4014° F), and has a specific gravity of 10.5. The atomic weight of silver is 107.868.

Chemically silver is not very active. It is insoluble in dilute acids and in alkalies but dissolves in concentrated nitric or sulfuric acid, and it does not react with oxygen or water at ordinary temperatures. Sulfur and sulfides attack silver, and tarnishing is caused by the formation of silver sulfide on the surface of the metal. Eggs, which contain a considerable quantity of sulfur as a constituent of protein, tarnish silver extremely quickly. Small amounts of sulfide, which occurs naturally in the atmosphere and which, as hydrogen sulfide (H2S), is added to natural gas used domestically, tarnish silver. The black silver sulfide (AG 2S) is among the most insoluble salts in aqueous solution, a property that is exploited for separating silver ions from other positive ions.

III. Occurrence
Silver ranks about 66th among elements in natural abundance in crustal rocks. It occurs in the pure state to a small extent; the most notable deposits of native silver are in Peru and Norway, where the mines have been worked for centuries. Pure silver is also found associated with pure gold in the form of an alloy known as electrum, and considerable amounts are recovered in the processing of gold. Silver is usually found combined with other elements (of which sulfur is the most predominant) in minerals and ores. Some of the important silver minerals are cerargyrite (or horn silver), pyrargyrite, sylvanite, and argentite. Silver also occurs as a constituent of lead, copper, and zinc ores, and half the world production of silver is obtained as a by-product in the processing of such ores. Practically all the silver produced in Europe is obtained from the lead sulfide ore, galena. In the United States relatively few mines are worked for their silver alone—the silver is mined in conjunction with lead, copper, and zinc. In 1988, U.S. mines produced an estimated 53 million troy oz. of silver, about 12 percent of the estimated 444 million troy oz. produced worldwide. Most of the silver mined in the world comes from Mexico, Peru, Canada, the United States, and Australia. The leading silver-producing states in the United States are Nevada, Idaho, Montana, and Arizona; they accounted for about 71 percent of the silver mined in the United States in 1989.

IV. Metallurgy

Silver is usually recovered from silver ores by roasting the ore in a furnace to convert the sulfides to sulfates and then chemically precipitating metallic silver. Several metallurgical processes are used to extract silver from ores of other metals. In the amalgamation process, liquid mercury, which forms an amalgam with the silver, is added to the crushed ore. After the amalgam is washed out of the ore the mercury is removed by distillation, leaving metallic silver. In lixiviation methods the silver is dissolved in a solution of a salt, usually sodium cyanide, after which metallic silver is precipitated by bringing the solution in contact with metallic zinc or aluminum. For the Parkes process, which is used extensively in separating silver from copper and lead ores, see Lead. The impure silver obtained in the metallurgical processes is usually refined by electrolytic methods or by cupellation, a process that involves removing impurities by vaporization or absorption.

V. Uses

The use of silver in jewelry, tableware, and as coinage is well known. The metal is usually alloyed with small amounts of other metals to make it harder and more durable. In the United States, coin silver was an alloy of 90 percent silver and 10 percent copper until 1965, when the silver content was reduced to 40 percent for half dollars; silver was eliminated from dimes and quarters after 1964. In 1970 the U.S. government sold the last of its marketable silver, which in earlier periods of U.S. economic history had been used to support a monetary system of bimetallism. Sterling silver for tableware and other solid-silver objects is 92.5 percent silver and 7.5 percent copper. Silver is used to coat smooth glass surfaces for mirrors by vaporization of the metal or by precipitation from a solution; however, aluminum has largely replaced silver in this application. Silver is also widely used in the circuitry of electrical and electronic components. Colloidal silver, dilute solutions of silver nitrate (AgNO3), and some insoluble compounds, such as potassium, are used in medicine as antiseptics and bactericides. Argyrol, a silver-protein compound, is a local antiseptic for the eyes, ears, nose, and throat.

The silver-halide salts—silver bromide, silver chloride, and silver iodide—which darken on exposure to light, are used in emulsions for photographic plates, film, and paper. The salts are soluble in sodium thiosulfate, which is the compound used in the photographic fixing process.

Contributed By: Seymour Z. Lewin, M.S., Ph.D., Professor of Chemistry, New York University.
"Silver," Microsoft® Encarta® Online Encyclopedia 2000 © 1997-2000 Microsoft Corporation. All rights reserved.

Silver as an Antimicrobial

Antimicrobial: Destroying or inhibiting the growth of microorganisms and especially pathogenic microorganisms (In Merriam-Webster Online Dictionary. Retrieved November 30, 2008)

Silver is widely used in topical gels and impregnated into bandages because of its wide-spectrum antimicrobial activity. The antimicrobial properties of silver stem from the chemical properties of its ionized form, Ag+. This ion forms strong molecular bonds with other substances used by bacteria to respire, such as molecules containing sulfur, nitrogen, and oxygen. Once the Ag+ ion complexes with these molecules, they are rendered unusable by the bacteria, depriving it of necessary compounds and eventually leading to the bacteria's death.

Silverplate: silver-plated objects may have a wide variety of marks, or may have no marks at all. The following terms all indicate an item is silver-plated: A1, AA, Coin Plate, Deepsilver or Deep Silver, Double or Double Plate, Electroplate, EP, EPC, EPBM, EPNS, EPWM, Extra Coin Plate, Extra Plate, Plate or Plated, Quadruple or Quadruple Plate, Reinforced Plate, Silver Plate or Silverplate, Silver Soldered, Sterling Inlaid, Sterling Plate, Triple or Triple Plate, XII, XIV, XS.

Silversmith: One who fashions silver objects and wrought items such as forged flatware. The first silversmiths who settled in this country set up our banking system and produced its first coinage.

Sinking: The hammering of a flat piece of metal into a concave hemispherical shape in the top of a tree stump or any dished form. A small bowl shape is formed in the center of the sheet producing a lip, enabling the piece to "ride" the end of a raising stake, aiding in the raising process.

Snarling: The embossing from underneath or inside an object with a long-armed steel tool, with one end placed in a vise. Snarling is accomplished by placing a form over the snarling iron's tip (which may be any shape) and tapping the back end of the arm which is secured in the vise. The vertical vibration that results gives a "kick," raising a bump on the outside of the object. This technique is usually used in conjunction with chasing.

Soldering:A process in which two or more metal items are joined together adhesively, by melting and flowing a filler metal into the joint, the filler metal having a relatively low melting point. Soft soldering is characterized by the melting point of the filler metal, which is below 800 °F. The filler metal used in the process is called solder. Soldering is distinguished from brazing by use of a lower melting-temperature filler metal; it is distinguished from welding by the base metals not being melted during the joining process. In a soldering process, heat is applied to the parts to be joined, causing the solder to melt and be drawn into the joint by capillary action and to bond to the materials to be joined by wetting action. After the metal cools, the resulting joints are not as strong as the base metal, but have adequate strength, electrical conductivity, and water-tightness for many uses.This technique does not possess the strength of brazing solders when joining higher temperature metals such as silver. See a soldering set-up here.

Spelter: While sometimes used merely as a synonym for zinc, is often used to identify a zinc alloy. In this sense it might be an alloy of equal parts copper and zinc used for hard soldering and brazing, or as an alloy, containing lead, that is used instead of bronze. In this usage it was common for many 19th-century cheap, cast articles such as candlesticks and clock cases and early 20th-century Art Nouveau ornaments and Art Deco figures.

Spinning: The first evidence of metal spinning techniques being used for the forming of metals occurs in the Middle Ages. During this time, the power for the lathe on which the vessels were being formed was provided by a second person turning a large wheel connected to the lathe spindle by belt. Only very thin, soft metals could be formed by the metal spinner with his stick-type tools. However, despite the limitations, this method of metal spinning represented a significant advance on the techniques used until then, which were limited to either casting or hammering.

Later, the metal spinning process advanced as both water power and steam power were used to drive the main spindle of the metal spinning lathe, but the hand spinner was still required to provide both the motive power and the forming skill necessary to transform a flat blank into the finished hollow component. This process was introduced to America about 1840.

The next step was the development of electric power assistance for the spinner so that he could concentrate solely on the metal spinning technique. The real breakthrough came with the use of the hydraulic power and the change from the stick-type tool to the use of a roller. This permitted the metal spinning of components in harder metals of heavier gauge and led to the development of the newer techniques of shear forming and flow forming. However, the final result on each component was still dependent on the skill of the individual operator and such factors as varying levels of concentration, fatigue, experience etc. 

Spring Hammer: A 5' cast iron beam supporting a long-handled, highly-polished pivoting hammer with a 3" diameter face. The hammer is mounted on a spring mechanism allowing the hammer head to bounce off a highly polished adjustable anvil used to flatten the bottoms of trays and anything else that requires a perfectly flat surface. The spring hammer head bounces off the anvil perfectly flat, avoiding a costly crescent-shaped miss-hit of a hand-held hammer head's edge. 

Stainless Steel: This is essentially a low carbon steel which contains at least 10% chromium by weight. It is this addition of chromium that gives the steel its unique stainless, corrosion-resisting properties. The chromium content of the steel allows the formation of a rough, adherent, invisible, corrosion-resisting chromium oxide film on the steel surface. If damaged mechanically or chemically, this film is self-healing, providing that oxygen, even in very small amounts, is present. The corrosion resistance and other useful properties of the steel are enhanced by increased chromium content and the addition of other elements such as molybdenum, nickel and nitrogen. Better quality stainless flatware contains 18% chromium and 8% nickel.

Carbon steel rusts when exposed to air and moisture. This iron oxide film (the rust) is active and accelerates corrosion by forming more iron oxide. Stainless steels have sufficient amounts of chromium present so that a passive film of chromium oxide forms which prevents further surface corrosion and blocks corrosion from spreading into the metal's internal structure.

Harry Brearley of the Brown-Firth research laboratory in Sheffield, England, is most commonly credited as the "inventor" of stainless steel. In 1913, while seeking a corrosion-resisting alloy for gun barrels.

Stake: Any polished cast iron or steel tool placed in a vise and is used for forming and planishing metal over. This tool is generally large enough to be used without a horse.

Sterling Silver: Most American sterling is marked Sterling, 925, or 925/1000. Sterling silver is a minimum of 925 parts pure silver to every 1000 parts. 

Prior to the enactment of the Stamping Act of 1906, there were no national laws requiring silver objects to be marked in any manner, although quite a few states had already adopted their own laws.  The Stamping Act of 1906 required all items being sold as sterling silver to be marked as sterling.

Prior to 1906, marking a piece Sterling or 925 was at the discretion of the maker. Most makers, however, were proud of the fact their objects were made of sterling, and boastfully marked their items as such.

A piece may be marked 935, 950, or with another higher grade. This is still considered sterling silver, but has a higher silver content than that required by the sterling standard of 925.

The term English Sterling was occasionally used on sterling objects during the coin silver era prior to 1868. 

Also during the time when coin silver was the predominant silver grade in the U.S., the Maryland Legislature passed the Assay Act, requiring all silver in Baltimore to be assayed. In 1830 the law was changed to no longer require the assaying of silver, but then required makers to mark their silver with quality designations. Silversmiths outside of Baltimore also started adopting this practice.  Sterling silver is 11 ounces 2 pennyweight silver per 12 ounces Troy, so sterling silver from this place and time is marked 11.2 or 11-2.

Surface Gauge: A vertical steel rod mounted with an adjustable arm fastened to a heavy base. The adjustable scribe-type pivoting arm can be raised or lowered to check the height or to scribe a level line around an object in order to mount a wire or anything else that must be level. Often used on top of a surface plate. 

Surface Plate: A perfectly level steel, cast iron or granite table of any dimension; used to check the level and flatness of an object. Often used in conjunction with the surface gauge. 

T-Stake: Any polished, cast iron or steel tool in the form of an elongated "T" and used in a vise for raising, forming or planishing metal. 

Taps & Dies: Metalworking taps and dies were often made by their users during the 18th and 19th centuries (especially if the user was skilled in toolmaking), using such tools as lathes and files for the shaping, and the smithy for hardening and tempering. Thus builders of, for example, locomotives, firearms, or textile machinery were likely to make their own taps and dies. During the 19th century the machining industries evolved greatly, and the practice of buying taps and dies from suppliers specializing in them gradually supplanted most such in-house work. Joseph Clement was one such early vendor of taps and dies, starting in 1828. With the introduction of more advanced milling practice in the 1860s and 1870s, tasks such as cutting a tap's flutes with a hand file became a thing of the past. In the early 20th century, thread-grinding practice went through significant evolution, further advancing the state of the art (and applied science) of cutting screw threads, including those of taps and dies. (Excerpted from Wikipedia)

Tarnish: Tarnish, in regards to silver, is a thin layer of corrosion that forms from a chemical reaction on the surface of an object. This layer consists mainly of black silver sulfide caused by the silver's reaction with sulfur-containing compounds such as hydrogen sulfide in the air. Tarnish appears as a yellow, gray, or black film on objects. After tarnish forms, the corrosion process slows as the silver sulfide layer thickens.

Any sulfur-containing compound with the sulfur in a reduced oxidation state (e.g., hydrogen sulfide, sulfur, carbonyl sulfide) will cause silver to tarnish. Moisture also plays a role. The higher the relative humidity, the faster silver tarnishes (if sulfur-containing compounds are present). However, even if there is no moisture in the air but it is contaminated with hydrogen sulfide, the silver will still tarnish because there is a direct reaction (water not involved) between the silver and the hydrogen sulfide. So it is not good enough to remove only the moisture because the silver will still tarnish if there is hydrogen sulfide present (or other tarnishing gases).

Clean silver will form tarnish more quickly than will tarnished silver.

Tussie-Mussie: A small, round bouquet of flowers and/or herbs. They are sometimes contained in a cone-shaped hand-held or lapel vessel.

Vermeil: A French term for a sterling object that is totally gold-plated. Also: silver-gilt (silver object entirely gold-plated) or silver parcel-gilt (silver object partially gold-plated).

Vinaigrette: A small metal perfume container usually made of gold or silver and containing a pierced metal tray beneath which was placed a piece of sponge soaked in an aromatic substance such as vinegar combined with lavender. Vinaigrettes were made as boxes and many more novel forms from the late 18th to the late 19th century. Most English examples were made in Birmingham.

Weighted Sterling: Reinforced holloware and dresserware. These pieces are most often filled with pitch, but may also contain plaster, lead, or some other material because the metal can be as thin as .003". If these pieces were not weighted, they would almost collapse! The total weight of the silver alone in a large candelabra may be as low as a few ounces. Weighted objects have been produced for decades, allowing more consumers to afford silver. In most cases, objects of this type are impractical because their structural integrity often suffers with daily use and cleaning. 

Well-and-Tree Platter: A large platter having a depressed design of a tree through which meat juices flow into a large depression at one end.

White Metal: An alloy of tin and other metals. White metals contain no silver. The following terms are for different types of white metal; some are trade names, others are generic terms:  Alaska Silver, Alpaca or Alpacca Silver, Aluminum Silver, Austrian Silver, Brazil or Brazilian Silver, Bristol Silver, Burmaroid Silver, England Silver, German Silver, Indian Silver, Japanese Silver, Laxey Silver, Mexican Silver, Nevada Silver, Nickel Silver, Paktong, Pearl Silver, Potosi Silver, Solid G Silver (aka German Silver), Sonora Silver, Tyrol Silver, Venetian Silver, Yukon Silver.