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Glossary 
De-mystifying the terms used by antique dealers, auctioneers and specialists.
 
There are 106 entries in this glossary.
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Term Main definition
Azurite
Copper carbonate ore.
Axminster

The first carpet company at Axminster, Devon, UK was established in 1755. It supplied a Chinoiserie carpet for the Brighton Pavilion and a Turkish one for Sir John Sloane´s House. In 1835 it closed and its equipment was taken over by the Wilton factory. Since then the term Axminster has applied to carpets produced mechanically by Wilton and those from the Kidderminster carpet factory.

Aventurine

A glass made by mixing copper crystals with molten glass. The process was discovered by chance at Murano in the 1500´s. The result is gold-like flecks in the, usually, coloured glass. A similar type was produced in antiquity, and the effect was also used in both Japanese and European lacquer making.

Automata
Animated figures, have been made since well before the time of Christ. In the Middle Ages, moving figures were often associated with clocks and bells in public places, as they still are today.
Autoclave
A strong vessel used for the lamination of glass under hugh pressure and controlled temperature conditions.
Austin
The company which stands out among post-war British pedal car manufacturers is Austin, which from the 1940´s produced small cars as well as large. The J40 Joy Cars were beautifully constructed and finished, and in unworn condition they are now comparatively scarce, and worth two thousand pounds plus. They were based on the design of the full-sized Austin Somerset and Devon, which also has fanatical followers. Still more desireable in the coveted eyes of adults nowadays are pedal racing cars such as the Pathfinder Special of about 1949. Alas those who found memories of them, the tinnier and less robust products of Tri-ang and other competitors have fewer fans these days and fetch much lower prices. 
Auction
Various Roman armies used to divide their loot and slaves by auction. In Britain the first record of auctioneering comes at the end of the 1400´s, with an official of Henry Vll´s court known as the King´s Over-Roper. To ´rope´was to shout out for sale (which might give one a ´ropey´throat) and the word survives in Scotland and Northern England where sales may be called ´roupes´. After the Restoration of Charles ll in 1660, auctions became common in London, with Covent Garden as the centre of the trade. Amongst the oldest Bbritish firms to survive are Sotheby´s, which stems from Baker´s book sales beginning in 1744, and Christie´s, founded in 1766. Dreweatt Neate of Newbury also has its origins in the 1760´s. Bohams, which is still in part a family-run firm, and Phillips, founded by James Christie´s sales clerk,followed at the end of the 1700´s. Other countries may have longer traditions, but today British auctioneers effectively sell up the world.
Attached Back
Attached back pieces feature cushions that are attached, and cannot be removed or flipped. Prevents pillows from being moved out of place. Attached back cushioning maintains the durability of cushioning because the back does not move or wear as it would if it were detached.
Astragal
In classical architecture this is a small semi-circular moulding, generally used with the Ionic Order. To cabinet makers however, an astragal is a glazing bar on the glass-fronted doors of case furniture such as bookcases and escritoires. It is also a small molding used to overlap or seal the joint where a pair of doors meet.
Assay
The testing of a metal or ore to determine its ingredients, purity and quality. The testing and proving of precious metals to verify that they contain only the legal proportion of base metal alloy. The Assay Office strikes the relevant marks as proof that it has been tested.
Ash
A tough light brown figured hardwood having a variety of shades in the grain. When polished up, it can resemble olive. It was used for making country furniture, cabinets and decorative veneers.

As Found or All Faults
A/F on a sale ticket is a warning: the piece is in some way defective, usually chipped, cracked or restored. As Is or As Bought are less common but may indicate that no claim is made as to date or origin.
Arts & Crafts
A 1800's movement, led by William Morris and his artist, and designer companions in UK which sought to challenge increasing industrialisation by re-introducing the medieval concepts of craftsmanship.
Art Nouveau
A new style, short lived and excessive, which thrived between c.1880 and 1914. It first appeared in Britain in the 1880’s and spread throughout Europe, particularly Belgium, France and Germany, in the early 1890s. It survived for 20 years, reflecting a return to nature and to the values of good workmanship. Known in Italy as stile Liberty, in Germany and Scandinavia asJugendstil, and Secession in Austria. The characteristics of Art Nouveau were drawn from nature and featured plants and flowers in sinuous curves and convolutions.
Art Deco
The first truly modern style which made full use of mechanised production and new materials. The name derives from the first major exhibition of decorative arts held after the First World War in 1925, L'Exposition Internationale des Arts Decoratifs et Industriels Modernes.
Arsenical Copper
Copper with phosphorus and arsenic additions that give good strength and resistance to fire cracking. It is used primarily for the manufacture of boiler fireboxes.
Arsenical Brass
Brass with improved corrosion resistance containing arsenic, and frequently aluminium.
Arrow Foot
This furniture foot style consists of a tapered cylinder that is separated from the leg by a turned ring. It is usually plain, even if the attached leg is fluted as shown in this example. A shorter, more squat variation is sometimes referenced as a blunt-arrow foot The arrow foot became popular in the mid-1700´s and is often featured in Hepplewhite  and Sheraton designs. It is especially characteristic of the Windsor Chair, typical of the work of furniture-makers in colonial Philadelphia.
Armour Plate Glass
Laminated glass, resistant to mechanical shock, composed of at least four panes of glass and usually at least 25 mm thick.
Armorial Porcelain
Primarily, this refers to Chinese export porcelain decorated with the coats of arms of European, American and Brazilian families. From around 1700, drawings and instructions were sent to the Jingdezhen factories, but the majority of the arms enamelled in the centre or rims of plates or on tureens and so on, were executed in Canton. As the decorators had no idea of what heraldry (or the written instructions) meant, so hilarious mistakes were frequently made. Complete services are uncommon but single pieces appear on the market not infrequently.
Armorial
Engraved crest or coat of arms
Armoire
A tall standing wardrobe or closet, often used to store clothes. It can feature one to three doors and sometimes a mirrored panel. The armoire  originated in France during the 1500's.
Arm Chair
An armchair can be any chair with with arm rests attached to each side. However, there are two different kinds: the fauteuil, with open sides, and the bergère, with closed sides. 
 
See also Fauteuil and Bergère
Arko Metal
80/20 brass
Ark
Large storage tank or container, e.g. Glaze Ark, Slip Ark, etc.
Argyll
A 1700's British gravy warmer, drum shaped like a tea pot or small coffee pot. The gravy was in a central cylinder connected to the spout, and surrounded by hot water. It was generally made of silver or other metals, but there are also pottery versions, notably in Wedgwood creamware. Argyles are recorded from about 1769, and are said to be named after the 4th Duke of Argyll.
 
See also Argyle
Argyle
A 1700's British gravy warmer, drum shaped like a tea pot or small coffee pot. The gravy was in a central cylinder connected to the spout, and surrounded by hot water. It was generally made of silver or other metals, but there are also pottery versions, notably in Wedgwood creamware. Argyles are recorded from about 1769, and are said to be named after the 4th Duke of Argyll.
 
See also Argyll
Argentan
Early name for nickel silver.
Architect´s Table
Otherwise known as an artist´s or draughtsman´s table. There were many variants in the 1700´s, but the common link is an adjustavle, rising, drawing board top. Usually there are slides, candle slides, draws and compartments for pens and ink pots. Some have central pillars and tripods, but usually they had four legs and storage space for sheets of Double Elephant paper (26.5 ins by 40 ins).
Arcading
Arcading is a carved architectural ornament in the shape of arches. It can be seen on chair-backs and applied on panels on coffers.
Arbalette

A serpentine form characteristic of the finest Louis XV commodes, buffets, and consoles.

Arabesque
Decoration of intricate interweaving, scrolling foliage, caligraphy or flowing lines, also known as Sarascenic or Moresque decoration. If it contains human figures it becomes Grotesque.
Apron
An apron is situated below the seat rail of a chair, settee, cabinets and tables, joining the surface of a chair or table with the legs. It can be referred to as a skirt and shaped like on this wonderful card table.
Apprentice Pieces
Technically known as ´prentices´pieces, these models of furniture, usually 8 inches to 10 inches long, are supposed to have been made by cabinetmakers as ´masterpieces´ to show their skills on completion of their apprenticeships. This may be true of some miniature pieces, but other examples served as travellers samples and shop window advertisements. Almost all small furniture is likely to have been intended for children and their dolls. In recent years at least one London firm of dealers in antique reproduction furniture has encouraged its craftsmen to make similar items.
Appraise
The process of estimating or assessing the value of a piece.
Applique
Applique or applied is a t erm used to describe an applied ornamental piece or a category of light that can be affixed to a wall. It is also a d ecoration that is ápplied´, or stuck on, to a surface, such as crests applied to the backs of chairs. A popular idea in the early Georgian period was for faceted, carved, turned or moulded ornaments to be applied to panels of doors or the flat surfaces of cabinets. Appliqué is fabric decorated in the same way, with shaped pieces forming a pattern on the material to which it is stitched.
Applied Work
Wire, moulding or cast pieces made separately and soldered on to the main body of a piece, to ornament or strengthen it. Decoration that is ápplied´, or stuck on, to a surface, such as crests applied to the backs of chairs. A popular idea in the early Georgian period was for faceted, carved, turned or moulded ornaments to be applied to panels of doors or the flat surfaces of cabinets. Appliqué is fabric decorated in the same way, with shaped pieces forming a pattern on the material to which it is stitched. 
See also Applique
Apparent Porosity
Relation between the volume of a mass and the volume of the water absorbed when the mass is immersed.
Apostle Spoon
A silver spoon terminating in a handle modelled as one of the apostles, made in UK and Germany between 1490 and 1675. In sets of 13, incorporating a Master spoon, with the figure of Christ.
Antlerite

Copper sulphide ore.

Antler Furniture
Antler and horn table and chairs became popular in Germany and Scotland during the mid 1800's. Chairs, in particular, look dangerous, as well as uncomfortable. In the United States, buffalo horns were used in a similar manner.
Antiquing
The use of finishes and other techniques to create the appearance of age. Antiquing can be applied to metal home accents, wooden pieces, and even leather to create an elegantly worn look.
Antique Glass
A trade term for glass more than 25 years old
Antique
A term used in the past to describe Greek and Roman artefacts, but since Victorian times it has widened to included anything over 100 years old. This is the legal definition for export and other purposes.
Antimony
Chemical symbol Sb One of the metals that may be alloyed with tin to create pewter. First used by British pewterers in the late 1600's. Historically known as ‘regulus’.
Anthemion
A classical flower motif (from the Greek anthos, a flower), resembling honeysuckle. It was much used in the 1700´s for architectural adornment and on furniture. Virtually indeistinguishable from the palmette, it was often used in conjunction with it by Adams and other neo-Classical designers.
Anode Copper
Cast slabs of copper from the fire refining processes used as starters for electrolytic refining.
See Copper 
Annealing
Process for restoring the malleability of silver and other metals that are made brittle by hammering. The metal is heated until red hot and then immersed into cold water.
 
Under natural conditions, the surface of molten glass will cool more rapidly than the centre. This results in internal stresses which may cause the glass sheet or object to crack, shatter or even explode some time later.
 
The annealing process is designed to eliminate or limit such stresses by submitting the glass to strictly controlled cooling in a special oven known as a "lehr". Inside the lehr, the glass is allowed to cool to a temperature known as the "annealing point". When the glass reaches this point, the lehr temperature is stabilized for a specific length of time (depending on the glass type, its thickness, its coefficient of expansion and the amount of residual stress required) to allow stresses present in the glass to relax. This phase is followed by a period of cooling with a pre-defined temperature gradient.
Annealed Glass
Under natural conditions, the surface of molten glass will cool more rapidly than the centre. This results in internal stresses which may cause the glass sheet or object to crack, shatter or even explode some time later.
 
The annealing process is designed to eliminate or limit such stresses by submitting the glass to strictly controlled cooling in a special oven known as a 'lehr'. Inside the lehr, the glass is allowed to cool to a temperature known as the 'annealing point'. When the glass reaches this point, the lehr temperature is stabilized for a specific length of time (depending on the glass type, its thickness, its coefficient of expansion and the amount of residual stress required) to allow stresses present in the glass to relax. This phase is followed by a period of cooling with a pre-defined temperature gradient.
Anneal
To cool glass by reintroducing a completed object into an auxiliary part of the glass furnace and slowly cooling the object so that any strain created in the glass during the forming process may be released. The critical area for cooling is 1000-800 degrees.
Aneroid Barometer
Áneroid´means ´containing no liquid´, and this form of barometer is so called bbecause it uses atmospheric pressure on a partial vacuum rather than on mercury. The invention goes back to Leibniz (1646-1716), but its first commercial use was by Lucien Vidie and his competitor, Eugéne Bourdon in the mid 1800´s. Desk or mantelpiece versions with visible workings were popular, and pocket types were also made in many sizes with gold, silver or brass cases. They should not be confused with anemometers or wind-gauges.
Andiron
Wrought iron or cast iron supports for logs, which were made in pairs from the 1400's to the 1700's , when coal replaced wood for heating most houses. They were vaguely dog-shaped, with upright stems, usually on two feet, and horizontal ´backs´ running to a hind foot. Most are simple and rustic , but great houses had grander versions in bronze, brass and even silver. Many of these were purely decorative, and were replaced by smaller, humbler versions for actual use.
 
The name andiron is thought to be a grammatical perversion of endiron. They are also known as Firedogs.

See also Firedogs

Ancient Glass
Generally refers to glass made before the Venetian era of glass making.
Amorphous
Non-crystalline, having no determinable form or crystalline structure, e.g. glass.
American Clock
The most commonly found American clocks in Britain is the mass produced, late 1800´s, wooden wall or mantel clock by the Ansonia Clock Co. They may have pediments or flat tops and painted or transfer-decorated panels below the dials. However, during the same period American makers were capable of better quality, and more impressive items were also exported.
Amboyna
A hard light reddish brown wood with a curled and mottled grain from the Moluccas Islands in South East Asia. It is used in was used for veneers in furniture marquetry.
Amber
A fossil resin chiefly found on the southern shore of the Baltic. Translucent, it has a rich, nicotine-yellowish-brown colour. It has been popular since the Middle Ages for decorative items and embellishments to furniture, as well as beads for jewellery.
Amalgam Gilding
The process used for the gilding of many copper alloys in ancient and historic times. Gold becomes pasty when mixed with mercury and may be applied as a paste over a surface. This can be followed by heating to drive off most of the mercury, or the mercury can be applied to the clean surface of the object to be gilded, followed by the attachment of gold leaf or foil. 
Amalgam
A compound or mixture of mercury with other metals. Mercury may form an amalgam with gold, silver, tin, zinc, lead, copper, and other metals. The microstructure of these amalgams may be complex. 
Aluminium Bronze

Copper-aluminium alloys with up to 13% of aluminium, usually also with other additions such as iron, manganese, nickel and/or silicon. These alloys are strong, hard and have excellent resistance to marine corrosion. They are therefore commonly used for making propellers, bearings, gears, valves, and pipe fittings for seawater use.

Aluminium Brass

High copper brass with aluminium added for improved corrosion resistance. This is often used for condenser tubes.

Aluminium

Al - Chemical symbol for Aluminium.

Element with atomic weight 26.98, atomic number 13, mp 660.37 ºC, specific gravity 2.69. It is the most abundant of the metallic elements but is very difficult to extract and was not properly known until 1827. 

Aluminium is an easy metal to polish. It is soft enough that even the roughest aluminium parts can be quickly polished to a bright shine.

Polished aluminium has a fault, it tarnishes quickly. Most factory polished aluminium parts are sprayed with a clear lacquer, acrylic or urethane to seal the part.

Like stainless steel, aluminium is relatively resistant to corrosion, but it is very susceptible to attack by strong acids and alkalis used in some cleaning products.

Alumina Silicate Glass

A special glass used for glass-to-metal seals, particularly suitable when operating temperatures of electrical components are high (up to 750°C). Alumina (aluminium oxide Al2O3) is added to the glass batch in the form of commonly found feldspars containing alkalis in order to help improve chemical resistance and mechanical strength, and to increase viscosity at lower temperatures.

Alphenide

Generic term for Nickel silver, also argentan.

Alpha Iron
See Ferrite 
Alpha Delta Eutectoid (in bronze)
A hard constituent normally present in the structure of cast bronze containing more than about 6% tin. (Delta phase intermetallic composition, Cu31Sn8).
Alpha Brass

An alloy of copper and zinc with no more than 38% zinc so that the beta phase is not formed. In antiquity, the cementation process for the manufacture of brass meant that only up to 28% zinc might be absorbed in the copper when the zinc ore was reduced in situ. Most ancient brasses do not contain over 28% zinc. 

Alpha Beta Brass
Brass containing over 36% of zinc or with other additions usually has two phases present in the crystal structure, alpha and beta. They are used for castings, extrusions and for hot stampings.  A brass with sufficient zinc present to allow the development of the beta phase. The equilibrium range of the alpha-beta composition varies with temperature being 33.5 to 36.8% at the solidus temperature, and 35 to 46.6 % at room temperature. As the beta to alpha reaction is a diffusion controlled reaction, it is relatively slow, thus it is possible to control the relative proportion of alpha to beta phases by a combination of composition and heat treatment so that the combination of tensile strength to ductility can be optimised. 
Alpakka
Brass with the addition of nickel, that has a strong bleaching property, and is extremely easy to work and resistant to corrosion. It is known under such names as Alpaca, Alpacca, Albata, Argentan, Baitong, German Silver, Maillechort, New Silver, Nickel Brass, Nickel Silver, Pakfong, Paktong, etc. and is an alloy consisting of mostly copper and other metals as follows:

Copper 55% approx.

Nickel 20% approx.
Zinc 20% approx.
Tin 05% approx. 
Alpakka is a very durable metal that can be polished to a high lustre shine. Acid will attack and dissolve the zinc causing pitting corrosion, so avoid contact with citric fruits and products containing acid.
Alluvial Deposit
The local concentration of minerals in old river and stream deposits (Alluvium). These form when minerals weathered and transported from the original solid geology deposits are locally concentrated in the bed of the stream. These stream deposits may be buried to some considerable depth below subsequent quaternary gravels. Tin and gold in particular are concentrated in such deposits. Much of the medieval and earlier tin mined in Devon and Cornwall came from stream works working this type of deposit. 
Alloy

A metallic mixture two or more elements. An alloy can be formed from a mixture of two or more metals e.g. copper and tin to form bronze, or by a mixture of a metallic and non-metallic element e.g. iron and carbon to form steel, or cast iron. 

It has been suggested that the term alloy should only be used when there is a suggestion that the mixing was deliberate. In the study of ancient metallurgy it is difficult to prove deliberate mixing in some cases, e.g. when the ‘alloy’ could have arisen by co-smelting e.g. Cu-As and Fe-C-P 1 alloys. So, an alternative use of the term would be - any metallic mixture of elements whose physical, mechanical, or metallurgical properties differed substantially from the constituent elements. 

In silver, the base metals are added for strength.

Allotropes of Iron

Iron as a solid exists in different allotropic crystalline forms. The most important are alpha iron (ferrite) and gamma iron (austenite). The crystal lattice arrangement of alpha iron is one which is body centred whereas that of gamma iron is a face-centred cubic arrangement. The iron-carbon equilibrium diagram (technically the iron-iron carbide meta-stable phase diagram) shows the temperature ranges in which each form of iron is most stable as well as the carbon solubility range for these allotropes or phases. 

The great importance of the two crystalline forms of iron lies in the difference of the solubility in solid solution of carbon between the two. Carbon is virtually insoluble in the body-centred ferrite form, the lattice structure of which will only accept a maximum of 0.04% of carbon. The face-centred cubic lattice of austenite will accept carbon atoms more readily and up to about 2.1% carbon is soluble in alpha iron. 

Alliotrope

Certain substances can exist in more than one crystalline form; for example carbon can be found as graphite, diamond, or the recently discovered buckminster-fullerene. Pure iron has three main allotropes alpha (ferrite) , and gamma (austenite) and delta, which are stable at different temperatures. 

All Wood Furniture
Constructed of wooden components; includes solids, veneered and engineered woods.
Alkali-Borosilicate Glass
A special glass used for glass-to-metal seals, particularly suitable when electrical qualities are not important.
Aliphatic Resin Glue

A popular yellow wood working glue.

Ale Warmer
Copper or brass vessel, tinned internally, shaped with a conical or bulbous foot suitable for use in a fire or grate to warm ale.  Copper Ale Warmers are found in various shapes and sizes but the most popular are those of shoe or conical shape. They were thrust into the ambers to prepare a welcome drink for a cold winters night.
Ale Flute

A tall, trumpet shaped glass with a long or short stem and spreading foot, used in the 1700´s Britain for beer and ale drinking. If engraved, the most common motif is the hop vine.

Alder

A light brown hardwood from the Birch family.

Albert Watch Chain
The Prince Consort (1819-1861), Queen Victoria´s husband, is commemorated in the name for a gold or silver watch chain, and also for a Flatware pattern.
Alabastron
Originally a small ancient Egyptian or Greek cosmetic bottle carved from alabaster. Later examples were made of glass, pottery and other materials. Cylindrical, with a round base and spreading rim, they are often iridescent after being buried for years.
Alabaster

Alabaster is a fine grained white, grey, yellow or reddish lime-stone, or form of the mineral gypsum which can be cut so thinly as to be translucent and polished to a smooth and waxy finish. It was even used for glazing small church windows in the Middle Ages. From the middle of the 1300's Nottingham was known as a centre for small-scale religious carvings in alabaster, but the British industry was killed in the 1500's by the Reformation. Often used in sculpture, decorative stone panelling, beads and cabochons.

Ajouré

Pierced, used to describe the surface of an ornament or element. Literally 'to let the light pass through.' feminine: ajourée.

Air Twist

A 1700's British method for stretching bubbles into single or double spirals in the stems of glasses. Sometimes the spirals were coloured.

Air Trap
An air-filled void, which may be of almost any shape. Air traps in stems are frequently tear-shaped or spirally twisted. Somtimes refered to as an Air Lock.
Ageing

Loose term covering some surface treatment techniques used to make objects look old. Also a metallurgical term to describe hardening an alloy by heating to a temperature where a precipitate forms from a super-saturated solid solution.

Age Hardening
The process of hardening spontaneously over time at ambient conditions. Some steels age-harden as do other alloys. The process was first studied in aluminium-copper where coherent precipitates of different structure form as the first stage of the process. 
Agate Ware

An agate like pottery made with blended clay by the Romans, and latterly by Wedgwood and other Staffordshire potters.

Agate Glass Jewellery
A Renaissance technique of blending molten glass of two or more colours to imitate semi-precious stones. The mixture was then turned into decorative objects, depending on the mix.
Agate Glass

A Renaissance technique of blending molten glass of two or more colours to imitate semi-precious stones. The mixture was then turned into decorative objects, depending on the mix.

Against You
This phrase is usually used by the auctioneer to make it plain to a bidder who is unsure where the bidding has got to and whether the bid is with him or not. He may repeat it several times for emphasis and if there is no forthcoming bid will sell to the last bidder.
Aesthetic Movement

This might be called the árty´end of the Arts and Crafts Movement. It was a reaction to the flamboyant ornamentations loved by the Victorians. From the 1840´s a new purity of design was championed by Pugin and Owen Jones, and in the 1860´s the ideal of Art for Art´s Sake was taken up by the culturally aware. The Movement drew on diverse sourses, from Japanese and Chinese to Queen Anne and traditional metalwork. Walter Crane summarised it well in 1889, “plain materials and surfaces are infinately preferable to inorganic or inappropriate ornament”.

Adnic

70% Copper, 29% nickel, 1% tin alloy for resistance to corrosion and heat.

Admiralty Brass

An out-dated term for an alpha brass in which some zinc is replaced by tin; usually only about 1-2% tin is added.

70/30 brass with 1% tin added for extra corrosion resistance.

Adam Style

Neo-classical style, first introduced into the UK by the Scottish architect/designer Robert Adam, typified by classical motifs such as palmettos and festoons

Acorn Cups

Cups made from silver and gold in the form of giant acorns, they were popular in the late 1500´and early 1600´s Britain. They are usually on twiggy stems, and the cover, the acorn itself, may well be engraved with a coat of arms. In the 1700´s and 1800´s the acorn appears in wood as a treen novelty, and sometimes in pottery for pepper and salt pots.

Acid Stamping

The process of acid etching a trademark or signature into glass after it has been annealed, using a device that resembles a rubber stamp.

Acid Polishing

A process used in the production of cut crystal to remove the opacity of etched surfaces where decoration has been applied. Items to be polished are immersed in a mixture of de-mineralized water, sulphuric acid and hydrofluoric acid, and then rinsed. There may be a single short immersion in a stronger solution or, alternatively, a series of immersions in a weaker solution.

Acid Etching

This process for the decoration of glass involves the application of hydrofluoric acid to the glass surface. Hydrofluoric acid vapours or baths of hydrofluoric acid salts may be used to give glass a matt, frosted appearance (similar to that obtained by surface sandblasting), as found in lighting glass. Glass designs can be produced by coating the glass with wax and then inscribing the desired pattern through the wax layer. When applied, the acid will corrode the glass but not attack the wax-covered areas.

Acanthus

Classical ornament in the form of a stylized leaf decoration based on the scalloped leaves of the acanthus plant. It was frequently found on furniture as carved decoration or cast bronze ornament, particularly from the French, Louis XVI period. The acanthus leaf decoration is also found on mahogany furniture from the Georgian, Victorian and Edwardian periods.

The acanthus leaf was the most prolific foliage to flourish as a decorative motif on architecture, furniture and works of art of all kinds. Derived from the Mediterranean acanthus spinosus, in the hands of artists it can also resemble thistle, poppy or parsley leaves. It is the basis of the Corinthian and Composite Orders, and easily turned into a scroll. Even Gothic and Romanesque architects and craftsmen employed it, and from the Renaissace to the mid 1800´s it was consistently in favour. Eventually, however, one critic was complaining of “the inevitable acanthus leaf as if in the whole range of vegetable life this was the only kind of foliage worth imitating”, and another that “it requires so little thought”.