Definitions terms of antiques or collectables, some are quite common and some not so common.
Definitions are from various sources.

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Gadroon:

Ornamentation used on silver and furniture formed by fluting or reeding or both, often in a spiral design.

Gallery:

Open fretwork or small balustrade forming a railing around the top of furniture

Gate Leg Table:

An early type of drop-leaf table in which the legs, connected by stretchers, from a swinging gate to support the leaves.

Gather:

In glassmaking, a globular mass of molten glass affixed to a blow-pipe, ready to be blown.

Georgian:

A term broadly used to refer to the style developed during the reigns of Georges I-IV

German Silver:

An alloy of copper, nickel, and zinc. Developed in England in mid 19th century.

Gesso:

Plaster of Paris applied to the surface of a piece to provide a smooth base for painting or gilding.

Girandole:

A wall mirror having candle branches as part of its structure

Gothic:

originally an architectural style characterized by the pointed arch, rib vault, and flying buttress; flourished from the eleventh to the 15th centuries, revived in the 18th century in furniture

Gouache:

opaque watercolor.

Guilloche:

enameling in which a metal surface is first engraved, then coated with translucent enamel that allows the pattern beneath to be seen.

Gouge Carving:

Early simple carving formed by repeating chisel cuts.

Grandfather Clock:

A tall case clock

Grandmother Clock:

A term for a miniature tall case clock

Graver:

An engraver's too; a burin

Grisaille

A for of decorative painting in shades of gray.

Guilloche:

An ornamental motif consisting of series of loosely interlacing, circular forms.

Hadley Chest:

An early chest with a hinged top and usually with one or two drawers, made in and around Hadley, Massachusetts, and decorated with overall, abstract floral carving and often with the owner's initials.

Hairy-Paw Foot:

A foot of a chair or any other seating form resembling the hairy paw of an animal.

Hallmarks:

The marks stamped on the English gold and silver to indicate its maker, date, origin, and quality.  There is thousands of various trademarks.

Handkerchief Table:

A triangular drop-leaf table with a triangular single leaf. When opened, it makes a square; closed it fits into a corner.

Hepplewhite:

An English furniture style characterized by graceful curves and light woods, named for George Hepplewhite, its creator.

Herringbone:

Decorative inlay composed of veneer cut obliquely and fitted together in a herringbone pattern

Highboy:

A modern term for a high chest of drawers comprised of two sections: an upper case, with drawers of varied depth and length, set upon a lower case, also with drawers, supported by legs.

High-Relief:

sculptured or cared work that stands out sharply from its background

Hollowware:

vessels such as silver and silver-plate bowls, vases, and pitchers

Horseshoe Seat:

A chair seat curved in a horseshoe or bell shaped, often used in Queen Anne chairs.

Imari Ware:

A type of Japanese porcelain exported from the port of Imari in the 17th and early 18th centuries.

Incunabula:

The earliest printed materials of any art or area. Primarily books before the year 1500.

Inlay:

Decoration formed by contrasting materials set into the surface of a piece.

Intaglio:

Designs depressed below the surface, opposite of relief.

Japonesque:

In the Japanese way or manner.

Japanning:

The process of simulating Oriental lacquer by the use of varnish or paint with decoration in low relief, usually in Chinoiserie designs.

Jewel work:

Carved ornamentation resembling cut gems

Joint Stool:

A small, backless seat with turned legs strengthened by stretchers.

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