glossary (A to E)
The definitions contained in this glossary have been distilled (and usually simplified) from published sources too numerous to mention here (most appear in our some books on glass section), and from information kindly provided by specialist dealers over the years, to whom many thanks. We believe the information to be accurate, but welcome corrections or suggestions for inclusion. The list of terms is by no means comprehensive, but we hope it contains most of the words that a beginner collector is likely to come across
click on any of the above to take you to entries beginning with that letter
(N.B. Headings in italics are Italian terms)
Acid-etching
Etching glass by applying hydrofluoric acid (neat, or in a diluted paste form - depending on the effect required) over an incised shellac or wax "resist". Equipment for incising the resist mechanically was invented by John Northwood of Stevens & Williams in about 1860, and a device for 'geometric' etching was developed in 1865
Acid-polishing
Modern (widely used since c 1880s, although originally patented in 1857 by W H, B & J Richardson) quick method of "polishing" cut glass by dipping in a mixture of hydrofluoric and sulphuric acid. Cheaper than mechanical polishing, but tends to "round off" cuts, thus losing definition
Air twist
A type of stem (popular c 1745-1770) where two or more bubbles in the gather are simultaneously drawn out and twisted to form hollow spirals in the stem. 19th Century imitations have ground-out pontils, flatter feet, and the metal is too bright
Ale glass
For drinking ale or beer, stemmed glass usually with rounded funnel or ogee bowl (3 to 5 fl oz capacity, slimmer than a contemporary wine glass). Often engraved with barley & hops motif
Annagelb
Yellow fluorescent glass (Uranium-tinted) invented by Josef Riedel (Bohemia) c 1830. Named for Anna (his wife) and gold
Annagrün
Greenish fluorescent glass, also invented by Josef Riedel c 1830
Annealing
Process by which a hot glass item is (after completion) uniformly re-heated and then gradually cooled down over many hours in the Lehr, in order to toughen it and make it less likely to crack when subjected to changes of temperature
Applied decoration
Hot glass added to a blown article, usually flowers, fruit, leaves or trailing
Art Déco
From 1925 Paris "Exposition Internationale des ARTs DÉCOratifs et Industriels Modernes".
Decorative style developed in 1920s & 1930s out of the Art Nouveau style, anti-functional and based on elegant craftsmanship, often with an emphasis on geometric patterns
Art glass
Decorative glass, which may or may not have a function, but which is essentially individually hand-blown, often as one-off or limited edition pieces. Sometimes referred to as Studio glass
Art Nouveau
First used by the connoisseur and dealer Samuel Bing as the name of his Paris gallery, which opened on 16th December 1895, it became the generic name for the decorative style current in 1890s and early 1900s, often assymetrical, and usually involving floral patterns with elaborately entwined tendrils. In Germany, it was known as Jugendstil (literally youth-style)
Aventurine
Inclusion of a suspension of copper particles, as in the man-made gemstone of the same name
Biedermeier
Name derived from early 19th Century cartoons of two smug bourgeois characters called "Biedermann" and "Bummelmeier" by the German satirist Ludwig Eichrodt. Subsequently used as an adjective to represent the style of decoration favoured by such people. Used in particular of Bohemian glass, often heavily-cut and/or with engraved, enamelled or gilded decoration, and popular between c 1815 and 1850
Biomorphic
Term used to describe much 1950s and later glass that has no regular or conventional form, but resembles shapes that occur in Nature
Blank
A plain glass object, usually hand-blown, intended for cutting, engraving, enamelling or gilding by a refiner. May also be cased
Blow-pipe
Hollow iron pipe onto which a gather of metal is placed and blown
Bowl
The upper part of the glass that holds the drink. May be engraved, enamelled, gilded, flashed, stained, cased and/or cut. See decanters & drinking-glasses
Bullicante
Containing a regular, controlled pattern of bubbles
Cameo
Similar to Hochschnitt, but using two or more layers of cased glass in different colours, the outer layer(s) being cut away to leave a design in relief (often flowers)
Cane
Rod of multicoloured glass, made up of smaller individual rods fused together, then stretched
Cased
Two or more substantial layers of different coloured glass blown over one another (one or more layers of which may be cut away to reveal the layer(s) beneath)
Casting
Ladling hot glass into a mould (often created by the Cire perdu process) and allowing to solidify before annealing
Cire Perdu
French for 'lost wax', whereby a model of the final article is produced manually in wax, then coated in clay or plaster before being heated until the wax liquefies and is drained off
Cluck-cluck
See Kuttrolf
Cold-enamelling
Enamels painted on to cold glass, but not fired (a cheap process, but the enamel is liable to wear off in time)
Colour twist
Rarer than opaque twist, red and green are the most common colours used, blue and yellow being extremely rare
Composite stem
Type of stem that includes elements of all the popular stems 1745-1775, combining plain sections, balusters, twists (very rarely opaque) and knops
Copper-wheel
Engraving using foot- or machine-powered small copper wheels coated with abrasive pastes
Cordial
Long-stemmed, small-bowled (1 to 1.5 fl oz) glass for drinking cordials and liqueurs from late 17th to late 19th Century
Corroso
Literally "corroded". A rough, stone-like finish to an article, achieved by exposing to acid fumes
Cottage glass
see Spatter glass
Crisselling
A 'disease' of glass, resulting first in a network of extremely fine crackles, and eventually the total disintegration of a piece. The 'cure' was discovered by George Ravenscroft in 1676, who added lead oxide to the batch
Cristallo
Thin, fragile Venetian soda glass c.15th Century, in which the addition of Manganese gave a clear, translucent rock crystal effect
Crizzling
see Crisselling
Crystal
See Lead crystal
Custard cup
Or custard glass; small bowl (sometimes with rudimentary stem & foot), usually with a single handle. Made from early 19th Century, for serving an individual portion of custard
Cut glass
Glass blanks, hand-cut on large iron or stone grinding-wheels and then polished
Dab handle
The modern style of handle (introduced in 1867), where the glass is applied first to the bottom anchor-point, then pulled upward and attached at the top (see also pump handle)
Decanter
Type of decorative bottle used for serving wine at table after being decanted from its original bottle to leave the dregs. Originally corked, glass stoppers introduced c 1730. Later used for serving spirits & cordials. See decanters & drinking-glasses
Deceptive glass
A drinking-glass, externally normal, the walls and/or base of the bowl being much thicker than usual so that the capacity is greatly diminished (thus allowing the drinker to appear to be drinking as much as others, while staying relatively sober!)
Diamond-cut
Method of cutting in parallel diagonal V-shaped grooves in two opposing directions, so as to leave faceted lozenge-shapes. Also imitated in pressed glass
Diamond-point
A method of hand-engraving by scratching or stipple-engraving glass with a diamond-pointed tool
Dip-mould
One-piece mould into which the gather is dipped before blowing, to give a particular surface effect such as a pattern of parallel or diamond-ribbing
Dram
Small inexpensive glass used in taverns for gin, brandy etc. Found with all types of stem (short) and bowl. 18th Century drams have conical foot (folded before 1750)
Dry mustard pot
Georgian (late 18th/early 19th Century) glass pot for holding powdered condiments, with a high-domed lid (to accommodate a spoon in between uses). May be plain, wrythen or cut, with various types of foot (including lemon-squeezer)
Dwarf ale glass
Small, rudimentary-stemmed funnel-shaped ale-glass. Ale being stronger in the 17th to early 19th centuries (more like a barley wine), ale glasses were often of quite small capacity
Enamels
Variously-coloured opaque or transparent pigments composed of glass powder, metallic oxides and a flux (e.g. borax). As in pottery glazes, the final colour was often not apparent until after firing
Enamelling
Process of painting enamels on to cold glass, then firing in a low-temperature kiln so that they fuse into the surface and are relatively resistant to wear
End-of-day glass
Produced (often by apprentices) by rolling a gather onto a random assortment of coloured glass fragments (literally, whatever was left at the end of the day) on the marver, then blowing and shaping (compare Spatter glass)
Engraving
see Copper-wheel, Diamond-point, Intaglio and Rock crystal
Etching
Decorating the surface of (usually thin) glass articles by means of scratching with a diamond-point or treating with acid
.. carry on to glossary (F to M)
