The hearth is the area within the brick fireplace opening upon which the Stove Grate or firedogs would have rested.

During the late 17th and much of the 18th century these were often formed from fire stone, frequently the soft, lightweight, Reigate stone. For the main entertaining rooms highly polished bright steel or brass, were used to form hearths. In the country, there is evidence of bricks being used, though towards the ends of the 18th century some hearths were made of York or Portland stone, but generally the predominant material used was fire stone.

Hearths were almost always fitted flush with the slab and flooring level, with their front edges abutting the back edge of the slab as indicated by the joint line in the image above. We have occasionally come across evidence of the use of brickwork to form the hearth but these tend to be either in more rural locations or later introductions which can be associated with efforts to raise the level of the hearth to prevent the fireplace from smoking.

Covings are used to protect the brickwork that forms the two side walls of the fireplace opening.

For much of the 18th century, these were used to reflect light from the burning fire out into the room. From the middle of the 17th and much of the 18th Century hand-made tin glazed tiles, often known as Delft or ‘Galley’ tiles, were used to cover the rough brickwork.

An alternative material used were slabs of marble set on edge sometimes with a moulding to the front edge and curved to the back. Known as cornerstones, by the 1740s these started being replaced with simpler architectural slabs known as covings. For less palatial buildings, Reigate and occasionally Portland stone sometimes painted white were used and commonly referred to as covings.

In the entertaining rooms within more imposing mansions and palaces, black marble from Namur or Derbyshire we used for covings. These two marbles have, once polished, highly reflective surfaces which reflected the light of the burning fire. By the end of the 18th century Reigate stone was extensively used for many chimney-pieces within London, and are frequently found flanking the sides of Pantheon and Bath Stove Grates, sometimes painted with stove grate polish, a black solution also with light-reflecting properties.

During the 18th Century the main fuel burned both in towns and also the country was coal which was transported mainly by sail from the mines on the North-East coast.

Wood was used but generally only in areas where it was not possible to utilise waterborne vessels for transport. Stove Grates were produced in London and provincial cities such as Leeds and Norwich as well as at the famous foundries of Carron in Scotland and Coalbrookdale in Shropshire.

Stove grates were mostly formed from a combination of wrought iron, wrought bright steel and cast iron sometimes with brass ornaments. The lower grates on which the coal rested were raised some distance above the hearth to allow a sufficient flow of air in underneath the fire.  In entertaining rooms these stove grates were highly polished and with the development of the industrial revolution, they increased in both their ornamental and technical features, so by the end of the 18th Century they burnt less fuel and generated more heat and more light. Wood tended to be burned at a lower level, the logs resting on wrought and cast bright metal supports known as firedogs (less commonly as andirons).

Stove grates also incorporated a mass of other decorative polished metals which were used to reflect the light from the burning fire out into the room. Stove grates come in a great variety of forms, ranging from very simple wrought iron grates with cast fire backs, to ingeniously designed examples. Most were designed to absorb the expansion caused by the extremes of the heat and many were highly ornamental such as the one above which is steel fronted, engraved and with raised bosses. Others are half height, pantheon, bath, forest or other forms, many were produced with hobs to the sides allowing a kettle to be boiled.

These design features evolved so that, by the third quarter of the 18th century, cast-iron fronted stove grates with raised ornamental detail, and incredibly decorative full front ‘register’ grates, were being produced with a multitude of cast or polished and engraved steel or brass surfaces. Some of these incorporated a number of advanced systems of heating water and warming air, and came with adjustable register plates to reduce the possibility of the burning fuel smoking. These adjustable register grates had the added advantage of being able to close the flue off completely, thereby preventing burglars from climbing down the chimney flues to break into houses!

The fireplace is the area within the brickwork opening of the chimney-breast where the stove grate sits on its hearth and the fire burns, allowing the smoke to pass up the flue.

This has an opening width, an opening height and an opening depth.

In the early 18th century the depth of these openings was considerable, sometimes as much as 28″ (712mm) but by the late 18th century the depth had been reduced to a broadly standard 18″(458mm). Many of these brick fireplaces were infilled with a quantity of mortar and bricks which secured the full-front ‘register’ stove grates that became fashionable from the 1770s.

The slab is the piece of fireproof stone or marble that projects out into the room at flooring level and upon which a fender or fireguard is placed.

At the end of the 17th and beginning of the 18th century, these slabs were commonly referred to as ‘Foot Paces’, and sometimes made of tiles. By the mid 1730s, the Foot Pace starts being replaced with the Masonry term, ‘Slab’. At the end of the 18th century slab projections in London were governed by the 1774 London Building Act and commonly had a minimum projection of 18 inches (458mm) or “one and one half foot paces” but increased in size for larger rooms. Slabs extend the full width of the Chimney-piece at flooring level and for many architecturally correct Palladian Chimney-pieces these projected to a depth equal to one half of their overall extent (often a considerable projection of 36″ or more (914mm)).

These marble slabs in the main entertaining rooms were originally polished to a high ‘glass’ finish, the polished slab reflecting the light from the fire out into the room provided one of the largest sources of light. Modern fire regulations are, in our experience, somewhat variable, but seem to generally require for operational fires, a minimum of 500mm in slab depth. For larger Chimney-pieces, a much greater projecting slab will add presence to a historic chimney-piece and accord far better with the dimensions and proportions of any historic room.

The slips are the two vertical and one horizontal non-combustible marble or stone sections which acted as a form of fire prevention for timber chimney-pieces.

The slips formed a barrier to prevent the fire from igniting the chimney-piece or any adjacent timber. It was common practice for each slip to be formed from two sections of marble or stone. The first, a facia, the second, returning at right angles to the facia into the fireplace opening. This provided additional fire protection as any stove grate would be located, as a result of the returns, back within the fireplace opening. Slips also provided a polished surface which, together with the slab, reflected the light out into the room.

There is some evidence to suggest that the horizontal top slip was occasionally referred to as the mantle. This may have been a hangover from the 17th Century. Its resurrection in the early 19th Century may lie with the interest in French architecture, the term mantle originating from French.

A Chimney-piece is a combination of elements that when assembled, form the architectural feature that surrounds the fireplace opening.

These are predominantly made from marble or stone (or when made of timber were supplied with a set of marble slips and sometimes plinth blocks). The Chimney-piece projects from the finished face of the chimney breast, and was the main focal point of most historic rooms for much of the 17th, 18th and 19th Centuries.

A Chimney-piece’s dimensions are generally identified as the width (or extent of the Cornice) and the height (overall from the level of the slab to the top of the Cornice).

The width of slab (generally the maximum projection of the chimney-piece at its base or flooring level), the aperture height, from the underside of the architrave to slab level. On timber chimney-pieces this is was reduced by the introduction of a marble or stone top slip commonly with a width of between 5-6”. The aperture width is the distance between the two inner sides of the architrave, which on timber chimney-pieces are commonly reduced again by between 10-12″ (254-305mm) to reflect the two side slips.

The terms used to describe the various elements of the chimney-piece and its installation and operation varied hugely between 1680 and 1830.

This was due in part to regional variations, as well as changes in language and of course, the vagaries of spelling. Thus during the late 17th and very early 18th century, Chimney Piece, Chimneypiece, Chimney-piece, Mantle-piece, Mantlepiece, Mantel Piece, and Mantel were all used to identify elements of a Chimney-piece.

By the late 1720s, the term Chimney-piece was in common use and was to remain so until the very end of the century when there is evidence that the term Mantel piece starts being used (probably resulting from the increased interest in French architecture at this time), but it was the Chimney-piece that was still the predominant term used during the rest of the 19th Century.

More recently additional terms have been in circulation, including Fireplace and Fire-surround. However the word Fireplace – generally refers only to the area in which the fire burns – the brick opening within the fabric of the building.