Stonemasonry is the craft of shaping rough pieces of rock into accurate geometrical shapes, mostly simple, but some of considerable complexity, and then arranging the resulting stones, often together with mortar, to form structures.
- Quarrymen split veins, or sheets of rock, and extract the resulting blocks of stone from the ground.
- Sawyers cut these rough blocks into cubes, to required size with diamond-tipped saws.
- Banker masons are workshop based, and specialise in carving stones into intricate geometrical shapes required by a building’s design. They can produce anything from stones with simple chamfers to tracery windows, detailed moldings and the more classical architectural building masonry. When working a stone from a sawn block, the mason ensures that the stone is bedded in the right way, so the finished work sits in the building in the same orientation as it was formed on the ground. The basic tools, methods and skills of the banker mason have existed as a trade for thousands of years.
- Carvers cross the line from craft to art, and use their artistic ability to carve stone into foliage, figures, animals or abstract designs.
- Fixer masons specialise in the fixing of stones onto buildings, using lifting tackle, and traditional lime mortars and grouts. Sometimes modern cements, mastics and epoxy resins are used, usually on specialist applications such as stone cladding. Metal fixings, from simple dowels and cramps to specialised single application fixings, are also used. The precise tolerances necessary make this a highly skilled job.
- Memorial masons or monumental masons carve gravestones and inscriptions. The modern stonemason undergoes comprehensive training, both in the classroom and in the working environment. Hands-on skill is complemented by intimate knowledge of each stone type, its application and best uses, and how to work and fix each stone in place. The mason may be skilled and competent to carry out one or all of the various branches of stonemasonry. In some areas the trend is towards specialisation, in other areas towards adaptability.
Types of stonemasonry
Types of stonemasonry are:
- Rubble Masonry: When roughly dressed stones are laid in a mortar the result is a stone rubble masonry.
- Ashlar Masonry: Stone masonry using dressed (cut) stones is known as ashlar masonry, whereas masonry using irregularly shaped stones is known as rubble masonry.
- Stone Veneer: Stone veneer is used as a protective and decorative covering for interior or exterior walls and surfaces. The veneer is typically 1 inch (2.54 cm) thick and must weigh less than 15 lb per square foot (73 kg m−2) so that no additional structural supports are required. The structural wall is put up first, and thin, flat stones are mortared onto the face of the wall. Metal tabs in the structural wall are mortared between the stones to tie everything together, to prevent the stonework from separating from the wall.
- Slipform Stonemasonry: Slipform stonemasonry is a method for making stone walls with the aid of formwork to contain the rocks and mortar while keeping the walls straight. Short forms, up to two feet tall, are placed on both sides of the wall to serve as a guide for the stone work. Stones are placed inside the forms with the good faces against the form work. Concrete is poured behind the rocks. Rebar is added for strength, to make a wall that is approximately half reinforced concrete and half stonework. The wall can be faced with stone on one side or both sides.
Traditionally medieval stonemasons served a seven-year apprenticeship. A similar system still operates today.
A modern apprenticeship lasts four years. This combines on-site learning through personal experience, the experience of the tradesmen and college work where apprentices are given an overall experience of the building, hewing and theory work involved in masonry. In some areas colleges offer courses which teach not only the manual skills but also related fields such as drafting and blueprint reading or construction conservationism. Electronic Stonemasonry training resources enhance traditional delivery techniques. Hands-on workshops are a good way to learn about stonemasonry also. Those wishing to become stonemasons should have little problem working at heights, possess reasonable hand-eye co-ordination, be moderately physically fit, and have basic mathematical ability. Most of these things can be developed while learning.
Stonemasons use a wide variety of tools to handle and shape stone blocks (ashlar) and slabs into finished articles. The basic tools for shaping the stone are a mallet, chisels, and a metal straight edge. With these one can make a flat surface – the basis of all stonemasonry.
Chisels come in a variety of sizes and shapes, dependent upon the function for which they are being used. There are different chisels for different materials and sizes of material being worked, for removing large amounts of material and for putting a fine finish on the stone.
Mixing mortar is normally done today with mortar mixers which usually use a rotating drum or rotating paddles to mix the mortar.
The masonry trowel is used for the application of the mortar between and around the stones as they are set into place. Filling in the gaps (joints) with mortar is referred to as pointing. Pointing in smaller joints can be accomplished using tuck pointers, pointing trowels, and margin trowels, among other tools.
A masons hammer has a long thin head and is called a Punch Hammer. It would be used with a chisel or splitter for a variety of purposes
A walling hammer can be used in place of a hammer and chisel or pincher to produce rubble or pinnings or snecks.
Stonemasons use a Lewis together with a crane or Block and tackle to hoist building stones into place.
Today power tools such as compressed-air chisels, abrasive spinners and angle grinders are much used: these save time and money, but are hazardous and require just as much skill as the hand tools that they augment. But many of the basic tools of stonemasonry have remained virtually the same throughout vast amounts of time, even thousands of years.
Stonemasonry is one of the earliest trades in civilisation’s history. During the time of the Neolithic Revolution and domestication of animals, people learned how to use fire to create quicklime, plasters, and mortars. They used these to fashion homes for themselves with mud, straw, or stone, and masonry was born.
The Ancients heavily relied on the stonemason to build the most impressive and long lasting monuments to their civilisations. The Egyptians built their pyramids, the civilisations of Central America had their step pyramids, the Persians their palaces, the Greeks their temples, and the Romans their public works and wonders among the famous ancient stonemasons is Sophroniscus, the father of Socrates, who was a stone-cutter.
Castle building was an entire industry for the medieval stonemasons. When the Western Roman Empire fell, building in dressed stone decreased in much of Western Europe, and there was a resulting increase in timber-based construction. Stone work experienced a resurgence in the 9th and 10th centuries in Europe, and by the 12th century religious fervour resulted in the construction of thousands of impressive churches and cathedrals in stone across Western Europe.
Medieval stonemasons’ skills were in high demand, and members of the guild, gave rise to three classes of stonemasons: apprentices, journeymen, and master masons. Apprentices were indentured to their masters as the price for their training, journeymen had a higher level of skill and could go on journeys to assist their masters, and master masons were considered freemen who could travel as they wished to work on the projects of the patrons. During the Renaissance, the stonemason’s guild admitted members who were not stonemasons, and eventually evolved into the Society of Freemasonry; fraternal groups which observe the traditional culture of stonemasons, but are not typically involved in modern construction projects.
A medieval stonemason would often carve a personal symbol onto their block to differentiate their work from that of other stonemasons. This also provided a simple ‘quality assurance’ system.
The Renaissance saw stonemasonry return to the prominence and sophistication of the Classical age The rise of the Humanist philosophy gave people the ambition to create marvellous works of art. The centre stage for the Renaissance would prove to be Italy, where city-states such as Florence erected great structures, including the Cathedral of Santa Maria, the Fountain of neptune and the Laurentian Library which was planned and built by Michelangelo Buonarroti, a famous stonemason of the Renaissance.
When Europeans settled the Americas, they brought the stonemasonry techniques of their respective homelands with them. Settlers used what materials were available, and in some areas stone was the material of choice. In the first waves, building mimicked that of Europe, to eventually be replaced by unique architecture later on.
In the 20th century, stonemasonry saw its most radical changes in the way the work is accomplished. Prior to the first half of the century, most heavy work was executed by draft animals or human muscle power. With the arrival of the internal combustion engine, many of these hard aspects of the trade have been made simpler and easier. Cranes and forklifts have made moving and laying heavy stones relatively easy for the stonemasons. Motor powered mortar mixers have saved much in time and energy as well. Compressed air powered tools have made working of stone less time-intensive. Petrol and electric powered abrasive saws can cut through stone much faster and with more precision than chiseling alone. Carbide-tipped chisels can stand up to much more abuse than the steel and iron chisels made by blacksmiths of old.