Stone sculpture is the result of forming 3-dimensional visually interesting objects from stone.

Carving stone

Stone carving

Stone carving is an ancient activity where pieces of rough natural stone are shaped by the controlled removal of stone. Owing to the permanence of the material, evidence can be found that even the earliest societies indulged in some form of stone work....

 into sculpture

Sculpture

Sculpture is three-dimensional artwork created by shaping or combining hard materials—typically stone such as marble—or metal, glass, or wood. Softer materials can also be used, such as clay, textiles, plastics, polymers and softer metals...

 is an activity older than civilization itself, beginning perhaps with incised images on cave walls. Prehistoric sculptures were usually human forms, such as the Venus of Willendorf

Venus of Willendorf

The Venus of Willendorf, also known as the Woman of Willendorf, is an high statuette of a female figure estimated to have been made between 24,000 and 22,000 BCE. It was discovered in 1908 by archaeologist Josef Szombathy at a paleolithic site near Willendorf, a village in Lower Austria near the...

 and the faceless statues of the Cycladic cultures of ancient Greece. Later cultures devised animal, human-animal and abstract

Abstract art

Abstract art uses a visual language of form, color and line to create a composition which may exist with a degree of independence from visual references in the world. Western art had been, from the Renaissance up to the middle of the 19th century, underpinned by the logic of perspective and an...

 forms in stone. The earliest cultures used abrasive techniques, and modern technology employs pneumatic hammers and other devices. But for most of human history, sculptors used hammer and chisel

Chisel

A chisel is a tool with a characteristically shaped cutting edge of blade on its end, for carving or cutting a hard material such as wood, stone, or metal. The handle and blade of some types of chisel are made of metal or wood with a sharp edge in it.In use, the chisel is forced into the material...

 as the basic tools for carving stone.

The process of stone sculpture

In the direct method of stone carving, the work usually begins with the selection of a stone for carving, the qualities of which will influence the artist's choices in the design process. The artist using the direct method may use sketches but eschews the use of a physical model. The fully dimensional form or figure is created for the first time in the stone itself, as the artist removes material, sketches on the block of stone, and develops the work along the way.

On the other hand is the indirect method, when the sculptor begins with a clearly defined model to be copied in stone. The models, usually made of plaster

Plaster

Plaster is a building material used for coating walls and ceilings. Plaster starts as a dry powder similar to mortar or cement and like those materials it is mixed with water to form a paste which liberates heat and then hardens. Unlike mortar and cement, plaster remains quite soft after setting,...

 or modeling clay, may be fully the size of the intended sculpture and fully detailed. Once the model is complete, a suitable stone must be found to fit the intended design. The model is then copied in stone by measuring with caliper

Caliper

A caliper is a device used to measure the distance between two opposing sides of an object. A caliper can be as simple as a compass with inward or outward-facing points...

s or a pointing machine

Pointing machine

A pointing machine is a measuring tool used by stone sculptors and woodcarvers to accurately copy plaster, clay or wax sculpture models into wood or stone....

. This method is frequently used when the carving is done by other sculptors, such as artisans or employees of the sculptor.

Some artists use the stone itself as inspiration; the Renaissance

Renaissance

The Renaissance was a cultural movement that spanned roughly the 14th to the 17th century, beginning in Italy in the Late Middle Ages and later spreading to the rest of Europe. The term is also used more loosely to refer to the historical era, but since the changes of the Renaissance were not...

 artist Michelangelo

Michelangelo

Michelangelo di Lodovico Buonarroti Simoni , commonly known as Michelangelo, was an Italian Renaissance painter, sculptor, architect, poet, and engineer who exerted an unparalleled influence on the development of Western art...

 claimed that his job was to free the human form hidden inside the block.

Roughing out

When he or she is ready to carve, the carver usually begins by knocking off, or "pitching", large portions of unwanted stone. For this task he may select a point chisel, which is a long, hefty piece of steel with a point at one end and a broad striking surface at the other. A pitching tool may also be used at this early stage; which is a wedge-shaped chisel with a broad, flat edge. The pitching tool is useful for splitting the stone and removing large, unwanted chunks. The sculptor also selects a mallet

Mallet

A mallet is a kind of hammer, usually of rubber,or sometimes wood smaller than a maul or beetle and usually with a relatively large head.-Tools:Tool mallets come in different types, the most common of which are:...

, which is often a hammer with a broad, barrel-shaped head. The carver places the point of the chisel or the edge of the pitching tool against a selected part of the stone, then swings the mallet at it with a controlled stroke. He must be careful to strike the end of the tool accurately; the smallest miscalculation can damage the stone, not to mention the sculptor’s hand. When the mallet connects to the tool, energy is transferred along the tool, shattering the stone. Most sculptors work rhythmically, turning the tool with each blow so that the stone is removed quickly and evenly. This is the “roughing out” stage of the sculpting process.

Refining

Once the general shape of the statue has been determined, the sculptor uses other tools to refine the figure. A toothed chisel or claw chisel has multiple gouging surfaces which create parallel lines in the stone. These tools are generally used to add texture to the figure. An artist might mark out specific lines by using calipers to measure an area of stone to be addressed, and marking the removal area with pencil, charcoal or chalk. The stone carver generally uses a shallower stroke at this point in the process. .

Final stages

Eventually the sculptor has changed the stone from a rough block into the general shape of the finished statue. Tools called rasps and rifflers are then used to enhance the shape into its final form. A rasp is a flat, steel tool with a coarse surface. The sculptor uses broad, sweeping strokes to remove excess stone as small chips or dust. A riffler is a smaller variation of the rasp, which can be used to create details such as folds of clothing or locks of hair.

The final stage of the carving process is polishing. Sandpaper can be used as a first step in the polishing process, or sand cloth. Emery

Emery (mineral)

Emery is a very hard rock type used to make abrasive powder. It largely consists of the mineral corundum , mixed with other species such as the iron-bearing spinels hercynite and magnetite, and also rutile...

, a stone that is harder and rougher than the sculpture media, is also used in the finishing process. This abrading, or wearing away, brings out the color of the stone, reveals patterns in the surface and adds a sheen. Tin and iron oxides are often used to give the stone a highly reflective exterior.

Types of stone used in carving

Soapstone

Soapstone

Soapstone is a metamorphic rock, a talc-schist. It is largely composed of the mineral talc and is thus rich in magnesium. It is produced by dynamothermal metamorphism and metasomatism, which occurs in the areas where tectonic plates are subducted, changing rocks by heat and pressure, with influx...

, with a Mohs hardness

Mohs scale of mineral hardness

The Mohs scale of mineral hardness characterizes the scratch resistance of various minerals through the ability of a harder material to scratch a softer material. It was created in 1812 by the German geologist and mineralogist Friedrich Mohs and is one of several definitions of hardness in...

 of about 2, is an easily worked stone, commonly used by beginning students of stone carving.

Alabaster

Alabaster

Alabaster is a name applied to varieties of two distinct minerals, when used as a material: gypsum and calcite . The former is the alabaster of the present day; generally, the latter is the alabaster of the ancients...

, African wonderstone, alberene, and softer kinds of serpentine, all about 3 on the Mohs scale, are more durable than soapstone. Alabaster, in particular, has long been cherished for its translucence.

Limestone

Limestone

Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....

 and sandstone

Sandstone

Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...

, at about 4 on the Mohs scale, are the only sedimentary

Sedimentary rock

Sedimentary rock are types of rock that are formed by the deposition of material at the Earth's surface and within bodies of water. Sedimentation is the collective name for processes that cause mineral and/or organic particles to settle and accumulate or minerals to precipitate from a solution....

 stones commonly carved. Limestone comes in a popular oolitic

Oolitic

Oolitic may refer to:* Oolite, a sedimentary rock consisting of ooids* Oolitic, Indiana, a town whose name came from the underlying limestone...

 variety, about twice as hard as alabaster, that is excellent for carving. The harder serpentines can also reach 4 on the Mohs scale.

Marble

Marble

Marble is a metamorphic rock composed of recrystallized carbonate minerals, most commonly calcite or dolomite.Geologists use the term "marble" to refer to metamorphosed limestone; however stonemasons use the term more broadly to encompass unmetamorphosed limestone.Marble is commonly used for...

, travertine

Travertine

Travertine is a form of limestone deposited by mineral springs, especially hot springs. Travertine often has a fibrous or concentric appearance and exists in white, tan, and cream-colored varieties. It is formed by a process of rapid precipitation of calcium carbonate, often at the mouth of a hot...

, and onyx

Onyx

Onyx is a banded variety of chalcedony. The colors of its bands range from white to almost every color . Commonly, specimens of onyx contain bands of black and/or white.-Etymology:...

 are at about 6 on the Mohs scale. Marble has been the preferred stone for sculptors in the European tradition ever since the time of classical Greece

Classical Greece

Classical Greece was a 200 year period in Greek culture lasting from the 5th through 4th centuries BC. This classical period had a powerful influence on the Roman Empire and greatly influenced the foundation of Western civilizations. Much of modern Western politics, artistic thought, such as...

. It is available in a wide variety of colors, from white through pink and red to grey and black.

The hardest stone frequently carved is granite

Granite

Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...

, at about 8 on the Mohs scale. It is the most durable of sculptural stones and, correspondingly, an extremely difficult stone to work.

Rough and unfinished statues

Rough block forms of unfinished statuary are known, and are in museums. Notable are the Akhenaten

Akhenaten

Akhenaten also spelled Echnaton,Ikhnaton,and Khuenaten;meaning "living spirit of Aten") known before the fifth year of his reign as Amenhotep IV , was a Pharaoh of the Eighteenth dynasty of Egypt who ruled for 17 years and died perhaps in 1336 BC or 1334 BC...

, Amarna Period

Amarna Period

The Amarna Period was an era of Egyptian history during the latter half of the Eighteenth Dynasty when the royal residence of the pharaoh and his queen was shifted to Akhetaten in what is now modern-day Amarna...

 statuary found at Akhetaten. One known sculptor, Thutmose (sculptor)

Thutmose (sculptor)

"The King's Favourite and Master of Works, the Sculptor Thutmose" , flourished 1350 BC, is thought to have been the official court sculptor of the Egyptian Pharaoh Akhenaten in the latter part of his reign...

, has his entire shop excavated at Akhetaten, with many unfinished block forms.