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Lapidary (from the
Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
) is the practice of shaping
stone
In geology, rock (or stone) is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its Chemical compound, chemical composition, and the way in which it is formed. Rocks ...
,
mineral
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2 ...
s, or
gemstones into decorative items such as
cabochon
A cabochon (; ) is a gemstone that has been shaped and polished, as opposed to faceted. The resulting form is usually a convex (rounded) obverse with a flat reverse. Cabochon was the default method of preparing gemstones before gemstone cutt ...
s,
engraved gem
An engraved gem, frequently referred to as an intaglio, is a small and usually semi-precious gemstone that has been carved, in the Western tradition normally with images or inscriptions only on one face. The engraving of gemstones was a major lux ...
s (including
cameos), and
facet
Facets () are flat faces on geometric shapes. The organization of naturally occurring facets was key to early developments in crystallography, since they reflect the underlying symmetry of the crystal structure. Gemstones commonly have facets cut ...
ed designs. A person who practices lapidary is known as a lapidarist. A lapidarist uses the lapidary techniques of cutting, grinding, and polishing.
Hardstone carving
Hardstone carving is a general term in art history and archaeology for the artistic carving of predominantly semi-precious stones (but also of gemstones), such as jade, rock crystal (clear quartz), agate, onyx, jasper, serpentinite, or carneli ...
requires specialized carving techniques.
In modern contexts, a gemcutter is a person who specializes in cutting diamonds, but in older contexts the term refers to artists who produced
hardstone carvings
Hardstone carving is a general term in art history and archaeology for the artistic carving of predominantly semi-precious stones (but also of gemstones), such as jade, rock crystal (clear quartz), agate, onyx, jasper, serpentinite, or carnelian, ...
; engraved gems such as jade carvings, a branch of miniature
sculpture
Sculpture is the branch of the visual arts that operates in three dimensions. Sculpture is the three-dimensional art work which is physically presented in the dimensions of height, width and depth. It is one of the plastic arts. Durable ...
or ornament in gemstone.
By extension, the term ''lapidary'' has sometimes been applied to collectors of and dealers in gems, or to anyone who is knowledgeable in precious stones.
Etymology
![Titlepage; The Expert Lapidary Wellcome L0064654](https://upload.wikimedia.org/wikipedia/commons/3/3a/Titlepage%3B_The_Expert_Lapidary_Wellcome_L0064654.jpg)
The etymological root of the word 'lapidary' is the Latin word , meaning "stone".
[Douglas Harper (2014)]
Lapidary
Online Etymology Dictionary In the 14th century, the term evolved from , meaning "stonecutter" or "working with stone", into the
Old French
Old French (, , ; Modern French: ) was the language spoken in most of the northern half of France from approximately the 8th to the 14th centuries. Rather than a unified language, Old French was a linkage of Romance dialects, mutually intellig ...
word , meaning "one skilled in working with precious stones".
[
In French, and later ]English
English usually refers to:
* English language
* English people
English may also refer to:
Peoples, culture, and language
* ''English'', an adjective for something of, from, or related to England
** English national ide ...
, the term is also used for a lapidary text, which was a treatise on precious stones that details their appearance, formation, and properties - particularly in terms of the powers believed to be held by some stones - as believed in medieval Europe. The beliefs about the powers of stones included their ability to prevent harm, heal ailments, or offer health benefits. 'Lapidary' appeared as an English adjective in the 18th century.[
]
History
The earliest known lapidary work likely occurred during the Stone Age. As people created tools from stone, they realized that some geological materials were harder than others. The next earliest documented examples of what could be considered lapidary arts came in the form of drilling stone and rock. The earliest roots of drilling rocks date back to approximately one million years ago.
The early Egyptians developed cutting and jewelry fashioning methods for lapis lazuli, turquoise
Turquoise is an opaque, blue-to-green mineral that is a hydrated phosphate of copper and aluminium, with the chemical formula . It is rare and valuable in finer grades and has been prized as a gemstone and ornamental stone for thousands of year ...
, and amethyst.
The art of lapidary was relatively well-developed in the Indian subcontinent
The Indian subcontinent is a list of the physiographic regions of the world, physiographical region in United Nations geoscheme for Asia#Southern Asia, Southern Asia. It is situated on the Indian Plate, projecting southwards into the Indian O ...
by the early 1st millennium CE. The surviving manuscripts of the 3rd century Buddhist text by Buddha Bhatta, and several Hindu texts of mid-1st millennium CE such as and , are Sanskrit
Sanskrit (; attributively , ; nominally , , ) is a classical language belonging to the Indo-Aryan branch of the Indo-European languages. It arose in South Asia after its predecessor languages had diffused there from the northwest in the late ...
treatises on lapidary arts. They discuss sources of gems and diamonds, their origins, qualities, testing, cutting and polishing, and making jewelry from them. Several other Sanskrit texts on gems and lapidary arts have been dated to post-10th century, suggesting a continuous lapidary practice.
According to Jason Hawkes and Stephanie Wynne-Jones
Stephanie Wynne-Jones is an Africanist archaeologist, whose research focuses on East African material culture, society and urbanism. She is Senior Lecturer and Deputy Head of the Department of Archaeology at the University of York. She previously ...
, archaeological evidence suggests that trade in lapidary products between Africa and India was established in the 1st millennium CE. People of the Deccan
The large Deccan Plateau in southern India is located between the Western Ghats and the Eastern Ghats, and is loosely defined as the peninsular region between these ranges that is south of the Narmada river. To the north, it is bounded by the ...
region of India and those near the coast of East Africa had innovated their own techniques for lapidary before the 10th century, as evidenced by excavations and Indian and non-Indian texts dated to that period.
Lapidary was also a significant tradition in early Mesoamerica
Mesoamerica is a historical region and cultural area in southern North America and most of Central America. It extends from approximately central Mexico through Belize, Guatemala, El Salvador, Honduras, Nicaragua, and northern Costa Rica ...
. The lapidary products were used as status symbols, for offerings, and during burials. They were made from shell
Shell may refer to:
Architecture and design
* Shell (structure), a thin structure
** Concrete shell, a thin shell of concrete, usually with no interior columns or exterior buttresses
** Thin-shell structure
Science Biology
* Seashell, a hard o ...
, jade, turquoise
Turquoise is an opaque, blue-to-green mineral that is a hydrated phosphate of copper and aluminium, with the chemical formula . It is rare and valuable in finer grades and has been prized as a gemstone and ornamental stone for thousands of year ...
, and greenstones. Aztec
The Aztecs () were a Mesoamerican culture that flourished in central Mexico in the post-classic period from 1300 to 1521. The Aztec people included different ethnic groups of central Mexico, particularly those groups who spoke the Nahuatl ...
lapidarists used string saws and drills made of reed and bone as their lapidary tools.
Techniques
There are three broad categories of lapidary arts: tumbling, cabochon cutting, and faceting
Stella octangula as a faceting of the cube
In geometry, faceting (also spelled facetting) is the process of removing parts of a polygon, polyhedron or polytope, without creating any new vertices.
New edges of a faceted polyhedron may be cre ...
. Among a modern gemcutter's work are the following activities:
* Positioning rough stone in a holder, and holding the stone against the edge of a revolving saw or lapidary slitter impregnated with diamond
Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Another solid form of carbon known as graphite is the chemically stable form of carbon at room temperature and pressure, ...
dust to cut and slit stone.
* Removing cut stone and placing it in lapidary stick. A gemcutter then selects the shaping wheel and applies abrasive compound. They hold a lapidary stick against the revolving shaping wheel and lapidary disk to further shape stone and grind facets.
* Depositing stone within a barrel with both water and a grinding/polishing medium and either vibrating or rotating said barrel using friction to grind and polish the stones over time.
* Examining stone for accuracy of cut, using a magnifying glass. A gemcutter polishes stone, using felt or canvas-covered polishing wheel, and polishing compounds, such as tripoli
Tripoli or Tripolis may refer to:
Cities and other geographic units Greece
*Tripoli, Greece, the capital of Arcadia, Greece
* Tripolis (region of Arcadia), a district in ancient Arcadia, Greece
* Tripolis (Larisaia), an ancient Greek city in ...
or jeweler's rouge.
* Possibly using a mechanical facet-cutting device. A gemcutter may cut and polish diamonds for industrial purposes, and be designated as an Industrial-Diamond Polisher (jewelry
Jewellery ( UK) or jewelry ( U.S.) consists of decorative items worn for personal adornment, such as brooches, rings, necklaces, earrings, pendants, bracelets, and cufflinks. Jewellery may be attached to the body or the clothes. From a w ...
-silver).
* The Mohs Hardness Scale is a commonly used tool in lapidary to help measure a minerals hardness. A minerals hardness is measured by seeing how easily scratched it is, and what other minerals on the Mohs Hardness scale can scratch it. This tool is helpful in indicating what different lapidary methods should be used on the material.
Cutting
Cutting of harder stones is done with a diamond-edged saw. For softer materials, a medium other than diamond can be used, such as silicon carbide, garnet
Garnets () are a group of silicate minerals that have been used since the Bronze Age as gemstones and abrasives.
All species of garnets possess similar physical properties and crystal forms, but differ in chemical composition. The different s ...
, emery, or corundum. Diamond cutting
Diamond cutting is the practice of shaping a diamond from a rough stone into a faceted gem. Cutting diamonds requires specialized knowledge, tools, equipment, and techniques because of its extreme difficulty.
The first guild of diamond cutters and ...
requires the use of diamond tools because of the extreme hardness of diamonds. The cutting, grinding, and polishing operations are usually lubricated with water, oil, or other liquids. Beyond these broader categories, there are other specialized forms of lapidary techniques, such as casting, carving, jewelry, and mosaic
A mosaic is a pattern or image made of small regular or irregular pieces of colored stone, glass or ceramic, held in place by plaster/mortar, and covering a surface. Mosaics are often used as floor and wall decoration, and were particularly pop ...
s.
While the gemstone in the rough state may be trimmed to remove undesirable material or to separate it on a cleavage line with a diamond blade
A diamond blade is a saw blade which has diamonds fixed on its edge for cutting hard or abrasive materials. There are many types of diamond blade, and they have many uses, including cutting stone, concrete, asphalt, bricks, coal balls, glass, an ...
d saw, accurately described as cutting and once done by the use of a chisel or similar tool to simply break off pieces that were usable as single gemstones, the actual shaping and polishing of a gemstone is a grinding or sanding
upright=1.35, Sheets of sandpaper with different grit sizes (40 (coarse), 80, 150, 240, 600 (fine)).
Sandpaper and glasspaper are names used for a type of coated abrasive that consists of sheets of paper or cloth with abrasive material glued to ...
process. This grinding and sanding is done using a lap
A lap is a surface (usually horizontal) created between the knee and hips of a biped when it is in a seated or lying down position. The lap of a parent or loved one is seen as a physically and psychologically comfortable place for a child to ...
, a precision metal plate embedded with grit similar to the more familiar embedding of grit on paper the lap is of high precision particularly for flatness and turned by a motor. The grit material is normally diamond and sometimes corundum for their hardness. Only diamond is hard enough on the Mohs scale
The Mohs scale of mineral hardness () is a qualitative ordinal scale, from 1 to 10, characterizing scratch resistance of various minerals through the ability of harder material to scratch softer material.
The scale was introduced in 1812 by th ...
to shape and polish a diamond.
Faceting
Faceting requires equipment allowing for very precise adjustment of angle and location around the gemstone for facet-placement, a process sometimes referred to as indexing.
The design may be computer-generated or left up to the skill and expertise of the individual cutting the gemstone.
During the process of grinding, faceting, and lapping, the gemstone is usually affixed ("dopped") to a rod (frequently referred to as a "dop" or "dopstick") made of wood, or perhaps brass or steel,
with dopping cement, a specialized thermal adhesive
Thermal adhesive is a type of thermally conductive glue used for electronic components and heat sinks. It can be available as a paste (similar to thermal paste) or as a double-sided tape.
It is commonly used to bond integrated circuits to heats ...
. The dopstick can be hand-held or inserted into the indexing equipment for more precise faceting. A coolant
A coolant is a substance, typically liquid, that is used to reduce or regulate the temperature of a system. An ideal coolant has high thermal capacity, low viscosity, is low-cost, non-toxic, chemically inert and neither causes nor promotes corrosi ...
then needs to be constantly applied to prevent softening of the cement. Diamonds, however, are held mechanically, or with low-melting point
The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depen ...
tin-lead solder, since the resultant heat generated by friction can be extreme, thus preventing the use of thermal adhesive
Thermal adhesive is a type of thermally conductive glue used for electronic components and heat sinks. It can be available as a paste (similar to thermal paste) or as a double-sided tape.
It is commonly used to bond integrated circuits to heats ...
s.
Cabochons - smooth-shaped gemstones without facets such as jade or turquoise
Turquoise is an opaque, blue-to-green mineral that is a hydrated phosphate of copper and aluminium, with the chemical formula . It is rare and valuable in finer grades and has been prized as a gemstone and ornamental stone for thousands of year ...
, and indeed most gemstones - are instead shaped and polished in much the same manner. They are usually left up to the skill and expertise of the individual cutting the gemstone and to similar equipment such as the lapping equipment.
Polishing
Most modern lapidary work is done using motorized equipment. Polishing is done with resin- or metal-bonded emery, silicon carbide
Silicon carbide (SiC), also known as carborundum (), is a hard chemical compound containing silicon and carbon. A semiconductor, it occurs in nature as the extremely rare mineral moissanite, but has been mass-produced as a powder and crystal s ...
(carborundum), aluminium oxide ( corundum), or diamond dust in successively decreasing particle sizes until a polish is achieved. In older systems, the grinding and polishing powders were applied separately to the grinding or buffing wheel. Often, the final polish will use a different medium such as tin oxide
Tin is a chemical element with the symbol Sn (from la, stannum) and atomic number 50. Tin is a silvery-coloured metal.
Tin is soft enough to be cut with little force and a bar of tin can be bent by hand with little effort. When bent, t ...
or cerium(IV) oxide
Cerium(IV) oxide, also known as ceric oxide, ceric dioxide, ceria, cerium oxide or cerium dioxide, is an oxide of the rare-earth metal cerium. It is a pale yellow-white powder with the chemical formula CeO2. It is an important commercial produc ...
.
The initial shaping and facet placement may be done using laps with grits of 220, 600, 1200. The polishing step, however, requires grits of a much higher grade, such as 8,000, 14,000, 50,000 and even 100,000. This grit is also embedded into a metal lap, but sometimes applied manually to the lap during polishing.
Inlaying
Another specialized form of lapidary work is the inlay
Inlay covers a range of techniques in sculpture and the decorative arts for inserting pieces of contrasting, often colored materials into depressions in a base object to form Ornament (art), ornament or pictures that normally are flush with th ...
ing of marble
Marble is a metamorphic rock composed of recrystallized carbonate minerals, most commonly calcite or dolomite. Marble is typically not foliated (layered), although there are exceptions. In geology, the term ''marble'' refers to metamorphose ...
and gemstones into a marble matrix. This technique is known in English as ''pietra dura
''Pietra dura'' () or ''pietre dure'' () ( see below), called parchin kari or parchinkari ( fa, ) in the Indian Subcontinent, is a term for the inlay technique of using cut and fitted, highly polished colored stones to create images. It is c ...
'', for the hardstones that are used, like onyx
Onyx primarily refers to the parallel banded variety of chalcedony, a silicate mineral. Agate and onyx are both varieties of layered chalcedony that differ only in the form of the bands: agate has curved bands and onyx has parallel bands. The ...
, jasper
Jasper, an aggregate of microgranular quartz and/or cryptocrystalline chalcedony and other mineral phases,Kostov, R. I. 2010. Review on the mineralogical systematics of jasper and related rocks. – Archaeometry Workshop, 7, 3, 209-213PDF/ref> ...
and carnelian
Carnelian (also spelled cornelian) is a brownish-red mineral commonly used as a semi-precious gemstone. Similar to carnelian is sard, which is generally harder and darker (the difference is not rigidly defined, and the two names are often used ...
. In Florence
Florence ( ; it, Firenze ) is a city in Central Italy and the capital city of the Tuscany Regions of Italy, region. It is the most populated city in Tuscany, with 383,083 inhabitants in 2016, and over 1,520,000 in its metropolitan area.Bilan ...
and Naples
Naples (; it, Napoli ; nap, Napule ), from grc, Νεάπολις, Neápolis, lit=new city. is the regional capital of Campania and the third-largest city of Italy, after Rome and Milan, with a population of 909,048 within the city's adminis ...
, where the technique was developed in the 16th century, it is called . The Medici Chapel at San Lorenzo in Florence is completely veneered with inlaid hard stones. The specialty of ''micromosaic
Micromosaics (or micro mosaics, micro-mosaics) are a special form of mosaic that uses unusually small mosaic pieces (tesserae) of glass, or in later Italian pieces an enamel-like material, to make small figurative images. Surviving ancient Roman ...
s'', which developed in the late-18th century in Naples and Rome, is sometimes covered under the umbrella term of lapidary work. In this technique, minute slivers of glass are assembled to create still life, cityscape views, and other images. In China, lapidary work specializing in jade carving has been continuous since at least the Shang dynasty
The Shang dynasty (), also known as the Yin dynasty (), was a Chinese royal dynasty founded by Tang of Shang (Cheng Tang) that ruled in the Yellow River valley in the second millennium BC, traditionally succeeding the Xia dynasty and ...
.
Safety
Stones can contain asbestos, silica, lead, talc, and other hazardous ingredients. The dust produced by lapidary techniques on such stones can cause health issues if inhaled. Copper(II) oxide
Copper(II) oxide or cupric oxide is an inorganic compound with the formula CuO. A black solid, it is one of the two stable oxides of copper, the other being Cu2O or copper(I) oxide (cuprous oxide). As a mineral, it is known as tenorite. It is ...
, which is common in colorful minerals such as turquoise and malachite, can damage the endocrine and central nervous
The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain and spinal cord. The CNS is so named because the brain integrates the received information and coordinates and influences the activity of all par ...
systems. The most common minerals are silicates, and the dust from these rocks can result in silicosis. Fossil rocks can be radioactive
Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is consi ...
.
For lapidary work, safety precautions include wearing a National Institute for Occupational Safety and Health
The National Institute for Occupational Safety and Health (NIOSH, ) is the United States federal agency responsible for conducting research and making recommendations for the prevention of work-related injury and illness. NIOSH is part of the C ...
approved respirator with replaceable cartridges and dust filters; using a local exhaust ventilation system or working outside; using proper lubricants; wearing protective clothing; showering and shampooing immediately afterward; and using a wet mop to clean the workshop.
Societies and clubs
There are lapidary club
Lapidary clubs promote popular interest and education in lapidary, the craft of working, forming and finishing stone, minerals and gemstones. These clubs sponsor and provide means for their members to engage in all forms of jewellery making, caboch ...
s throughout the world. In Australia, there are numerous gem shows, including an annual gem show called the GEMBOREE, which is a nationwide lapidary competition. There is a collection of gem and mineral shows held in Tucson, Arizona
, "(at the) base of the black ill
, nicknames = "The Old Pueblo", "Optics Valley", "America's biggest small town"
, image_map =
, mapsize = 260px
, map_caption = Interactive map ...
, at the beginning of February each year. The event began with the Tucson Gem and Mineral Society Show and has now grown to include dozens of other independent shows. In 2012, this concurrent group of shows constituted the largest gem and mineral event in the world.
In the United States, societies include the American Gem Society
The American Gem Society (AGS) is a trade association of retail jewelers, independent appraisers, suppliers, and selective industry members, which was founded in 1934 by Robert M. Shipley.
The Society is based in Las Vegas, Nevada, along with th ...
.
See also
*Amber
Amber is fossilized tree resin that has been appreciated for its color and natural beauty since Neolithic times. Much valued from antiquity to the present as a gemstone, amber is made into a variety of decorative objects."Amber" (2004). In ...
*Diamantaire
A diamantaire (''French origin'') is a gem-quality diamond manufacturer or producer, master diamond cutter, and graduate gemologist specializing in diamonds.
Such individuals demonstrate considerable expertise in different types of gemstones, pa ...
*Diamond
Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Another solid form of carbon known as graphite is the chemically stable form of carbon at room temperature and pressure, ...
*Diamond cutting
Diamond cutting is the practice of shaping a diamond from a rough stone into a faceted gem. Cutting diamonds requires specialized knowledge, tools, equipment, and techniques because of its extreme difficulty.
The first guild of diamond cutters and ...
* Gemstone
*Handicraft
A handicraft, sometimes more precisely expressed as artisanal handicraft or handmade, is any of a wide variety of types of work where useful and decorative objects are made completely by one’s hand or by using only simple, non-automated re ...
* Jade
*Lapping
Lapping is a machining process in which two surfaces are rubbed together with an abrasive between them, by hand movement or using a machine.
Lapping often follows other subtractive processes with more aggressive material removal as a first ste ...
*Pearl
A pearl is a hard, glistening object produced within the soft tissue (specifically the mantle) of a living shelled mollusk or another animal, such as fossil conulariids. Just like the shell of a mollusk, a pearl is composed of calcium carb ...
*Ruby
A ruby is a pinkish red to blood-red colored gemstone, a variety of the mineral corundum ( aluminium oxide). Ruby is one of the most popular traditional jewelry gems and is very durable. Other varieties of gem-quality corundum are called ...
*Sandpaper
upright=1.35, Sheets of sandpaper with different grit sizes (40 (coarse), 80, 150, 240, 600 (fine)).
Sandpaper and glasspaper are names used for a type of coated abrasive that consists of sheets of paper or cloth with abrasive material glued to ...
References
{{Authority control
Hardstone carving
Jewellery making