Lapidary

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Examples of lapidary products Lapidary 3302.jpg
Examples of lapidary products
Gemcutting in Thailand Thai Gem Cutting.jpg
Gemcutting in Thailand

Lapidary (from the Latin lapidarius) is the practice of shaping stone, minerals, or gemstones into decorative items such as cabochons, engraved gems (including cameos), and faceted designs. A person who practices lapidary is known as a lapidarist. A lapidarist uses the lapidary techniques of cutting, grinding, and polishing. [1] [2] [3] Hardstone carving requires specialized carving techniques. [2]

Contents

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; engraved gems such as jade carvings, a branch of miniature sculpture 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. [4]

Etymology

A 17th century English lapidary text Titlepage; The Expert Lapidary Wellcome L0064654.jpg
A 17th century English lapidary text

The etymological root of the word lapidary is the Latin word lapis, meaning "stone". [5] In the 14th century, the term evolved from lapidarius, meaning 'stonecutter' or 'working with stone', into the Old French word lapidaire, meaning 'one skilled in working with precious stones'. [5]

In French, and later English, 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. [6] Lapidary appeared as an English adjective in the 18th century. [5]

History

Lapidary tool kit from around 900 AD, Chaco Culture National Historical Park Lapidary tool kit, NPS.jpg
Lapidary tool kit from around 900 AD, Chaco Culture National Historical Park

The earliest known lapidary work likely occurred during the Stone Age. [1] [7] 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. [8]

The early Egyptians developed cutting and jewelry fashioning methods for lapis lazuli, turquoise, and amethyst. [9]

The art of lapidary was relatively well-developed in the Indian subcontinent by the early 1st millennium CE. The surviving manuscripts of the 3rd century Buddhist text Rathanpariksha by Buddha Bhatta,[ citation needed ] and several Hindu texts of mid-1st millennium CE such as Agni Purana and Agastimata, are Sanskrit treatises on lapidary arts. They discuss sources of gems and diamonds, their origins, qualities, testing, cutting and polishing, and making jewelry from them. [10] [11] [12] Several other Sanskrit texts on gems and lapidary arts have been dated to post-10th century, suggesting a continuous lapidary practice. [13]

According to Jason Hawkes and Stephanie Wynne-Jones, archaeological evidence suggests that trade in lapidary products between Africa and India was established in the 1st millennium CE. People of the Deccan 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. [14]

Lapidary was also a significant tradition in early Mesoamerica. The lapidary products were used as status symbols, for offerings, and during burials. They were made from shell, jade, turquoise, and greenstones. Aztec lapidarists used string saws and drills made of reed and bone as their lapidary tools. [15]

Medieval lapidaries

The history of lapidaries can be traced back to the classical world, where writers like Theophrastus and Pliny the Elder laid the foundations for later medieval interpretations of gemstones. In his examination of lyngurium—a mythical gemstone described by Theophrastus—Steven A. Walton discusses how classical knowledge was transmitted and adapted in medieval lapidary traditions. Despite the mythical nature of some of these stones, medieval lapidaries continued to draw on classical sources, blending scientific knowledge with magical beliefs. Walton highlights how these texts cataloged stones not only for their aesthetic and material properties but also for their purported magical and medicinal functions, making lapidaries sources essential for texts for both scholars and practitioners of natural philosophy during the medieval period. [16]

In Anglo-Saxon England, lapidaries became particularly significant as both medical and religious guides. Peter Kitson traces the transmission of lapidary knowledge into early medieval England, emphasizing how these texts informed by Lapidaries functioned as practical manuals for physicians, clergy, and scholars. The Old English Lapidary, for instance, detailed the healing properties of stones, reflecting the belief that gemstones could cure illnesses and provide spiritual protection. Kitson argues that lapidaries in this period served a dual purpose: they were not only scientific texts that described natural phenomena but also moral and religious guides that connected material objects to divine forces. [17]

Medieval lapidaries were deeply embedded in the practice of lithotherapy, the belief in the healing properties of stones. John M. Riddle’s analysis of lithotherapy in the Middle Ages emphasizes the medical role lapidaries played, particularly in guiding the use of gemstones for healing. These texts described how different stones, often categorized by color, composition, and astrological associations, could be used to treat specific ailments. Riddle points out that medieval lapidaries were not merely collections of folklore; they were often considered legitimate medical texts, consulted by physicians and healers to guide treatment practices. [18]

The Peterborough Lapidary is another example of a medieval lapidary that reflects the blending of practical and mystical knowledge. As detailed in A Medieval Book of Magical Stones: The Peterborough Lapidary, this text catalogs various gemstones and their magical properties, emphasizing the belief that stones could influence human behavior, protect against harm, and even cure diseases. The Peterborough Lapidary demonstrates how lapidaries were used not only for healing but also for magical and protective purposes, reflecting the medieval understanding that the natural world was imbued with supernatural power. [19]

Lapidaries also played an important role in medieval spirituality. Richard A. Beinert’s analysis of medieval piety and lapidary literature emphasizes how these texts reflected religious beliefs. Medieval Christians often associated gemstones with biblical figures, virtues, and divine forces. Lapidaries like the Peterborough Lapidary reinforced the idea that stones had sacred meanings, offering protection and spiritual benefits to those who used them correctly. Beinert suggests that these texts served as “windows on a medieval world” where natural objects were seen as manifestations of divine power, bridging the gap between the material and the spiritual. [20]

Several notable examples of medieval lapidaries highlight their widespread use and cultural significance. The Lapidary of Sydrac, a 13th-century text, stands out for its inclusion of unusual lore about gemstones. William M. Holler notes that the Lapidary of Sydrac cataloged not only conventional healing properties of stones but also fantastical claims, such as stones that could grant invincibility or manipulate human emotions. This text reflects the broader medieval belief in the mystical powers of nature and the importance of lapidaries in transmitting both empirical knowledge and magical traditions. [21]

In literary contexts, lapidary traditions also made their way into poetry. Tony Davenport’s analysis of the medieval poem Pearl reveals how the symbolic meanings of gemstones, as described in lapidaries, informed the poem’s themes of loss, beauty, and spiritual transcendence. Davenport suggests that the portrayal of jewels in Pearl draws on lapidary traditions to convey deeper religious and moral messages, illustrating how lapidary knowledge permeated not only scientific and medical texts but also literary and artistic works. [22]

Techniques

A jewellery worker in Sri Lanka Zafirs-treball2.jpg
A jewellery worker in Sri Lanka

There are three broad categories of lapidary arts: tumbling, cabochon cutting, and faceting. Among a modern gemcutter's work are the following activities:

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, emery, or corundum. Diamond cutting 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 mosaics.[ citation needed ]

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 bladed 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 process. This grinding and sanding is done using a lap, 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 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. The dopstick can be hand-held or inserted into the indexing equipment for more precise faceting. A coolant then needs to be constantly applied to prevent softening of the cement. Diamonds, however, are held mechanically, or with low-melting point tin-lead solder, since the resultant heat generated by friction can be extreme, thus preventing the use of thermal adhesives.

Cabochons - smooth-shaped gemstones without facets such as jade or turquoise, 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 (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 or cerium(IV) oxide.

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 inlaying of marble and gemstones into a marble matrix. This technique is known in English as pietra dura , for the hardstones that are used, like onyx, jasper and carnelian. In Florence and Naples, where the technique was developed in the 16th century, it is called opere di commessi. The Medici Chapel at San Lorenzo in Florence is completely veneered with inlaid hard stones. The specialty of micromosaics , 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.[ citation needed ]

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. [25] Copper(II) oxide, which is common in colorful minerals such as turquoise and malachite, can damage the endocrine and central nervous systems. The most common minerals are silicates, and the dust from these rocks can result in silicosis. Fossil rocks can be radioactive. [26]

For lapidary work, safety precautions include wearing a National Institute for Occupational Safety and Health 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. [26]

Societies and clubs

There are lapidary clubs 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 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. [ citation needed ]

In the United States, societies include the American Gem Society.

See also

Related Research Articles

<span class="mw-page-title-main">Diamond</span> Form of carbon

Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Diamond as a form of carbon is a tasteless, odourless, strong, brittle solid, colourless in pure form, a poor conductor of electricity, and insoluble in water. Another solid form of carbon known as graphite is the chemically stable form of carbon at room temperature and pressure, but diamond is metastable and converts to it at a negligible rate under those conditions. Diamond has the highest hardness and thermal conductivity of any natural material, properties that are used in major industrial applications such as cutting and polishing tools. They are also the reason that diamond anvil cells can subject materials to pressures found deep in the Earth.

<span class="mw-page-title-main">Gemstone</span> Piece of mineral crystal used to make jewelry

A gemstone is a piece of mineral crystal which, when cut or polished, is used to make jewelry or other adornments. Certain rocks and occasionally organic materials that are not minerals may also be used for jewelry and are therefore often considered to be gemstones as well. Most gemstones are hard, but some softer minerals such as brazilianite may be used in jewelry because of their color or luster or other physical properties that have aesthetic value. However, generally speaking, soft minerals are not typically used as gemstones by virtue of their brittleness and lack of durability.

<span class="mw-page-title-main">Mohs scale</span> Qualitative scale characterizing scratch resistance

The Mohs scale of mineral hardness is a qualitative ordinal scale, from 1 to 10, characterizing scratch resistance of minerals through the ability of harder material to scratch softer material.

<span class="mw-page-title-main">Topaz</span> Silicate mineral

Topaz is a silicate mineral made of aluminum and fluorine with the chemical formula Al2SiO4(F, OH)2. It is used as a gemstone in jewelry and other adornments. Common topaz in its natural state is colorless, though trace element impurities can make it pale blue or golden brown to yellow-orange. Topaz is often treated with heat or radiation to make it a deep blue, reddish-orange, pale green, pink, or purple.

<span class="mw-page-title-main">Ruby</span> Variety of corundum, mineral, gemstone

Ruby is a pinkish red to blood-red colored gemstone, a variety of the mineral corundum. Ruby is one of the most popular traditional jewelry gems and is very durable. Other varieties of gem-quality corundum are called sapphires. Ruby is one of the traditional cardinal gems, alongside amethyst, sapphire, emerald, and diamond. The word ruby comes from ruber, Latin for red. The color of a ruby is due to the element chromium.

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.

<span class="mw-page-title-main">Cabochon</span> Gemstone that has been shaped and polished

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 cutting developed.

An abrasive is a material, often a mineral, that is used to shape or finish a workpiece through rubbing which leads to part of the workpiece being worn away by friction. While finishing a material often means polishing it to gain a smooth, reflective surface, the process can also involve roughening as in satin, matte or beaded finishes. In short, the ceramics which are used to cut, grind and polish other softer materials are known as abrasives.

<span class="mw-page-title-main">Facet</span> Flat surface of a gem, crystal, etc.

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 into them in order to improve their appearance by allowing them to reflect light.

<span class="mw-page-title-main">Stone carving</span> The act of shaping stone materials

Stone carving is an activity where pieces of rough natural stone are shaped by the controlled removal of stone. Owing to the permanence of the material, stone work has survived which was created during our prehistory or past time.

<span class="mw-page-title-main">Amateur geology</span> Non-professional study and collecting of rocks

Amateur geology or rock collecting is the non-professional study and hobby of collecting rocks and minerals or fossil specimens from the natural environment. In Australia, New Zealand and Cornwall, the amateur geologists call this activity fossicking. The first amateur geologists were prospectors looking for valuable minerals and gemstones for commercial purposes. Eventually, however, more people have been drawn to amateur geology for recreational purposes, mainly for the beauty that rocks and minerals provide.

<span class="mw-page-title-main">Diamond simulant</span> Diamond-like object which is not a diamond

A diamond simulant, diamond imitation or imitation diamond is an object or material with gemological characteristics similar to those of a diamond. Simulants are distinct from synthetic diamonds, which are actual diamonds exhibiting the same material properties as natural diamonds. Enhanced diamonds are also excluded from this definition. A diamond simulant may be artificial, natural, or in some cases a combination thereof. While their material properties depart markedly from those of diamond, simulants have certain desired characteristics—such as dispersion and hardness—which lend themselves to imitation. Trained gemologists with appropriate equipment are able to distinguish natural and synthetic diamonds from all diamond simulants, primarily by visual inspection.

A faceting machine is broadly defined as any device that allows the user to place and polish facets onto a mineral specimen. Machines can range in sophistication from primitive jamb-peg machines to highly refined, and highly expensive, commercially available machines. A major division among machines is found between those that facet diamonds and those that do not. Specialized equipment is required for diamond faceting, and faceting as an occupation rarely bridges the gap between diamond and non-diamond workmanship. A second division can be made between industrial faceting and custom/hobby faceting. The vast majority of jewelry-store gemstones are faceted either abroad in factories or entirely by machines. Custom jewelry is still commonly made of custom metalwork and mass-produced gemstones, but unusual cuts or particularly valuable gemstone material will likely be faceted on a personal faceting machine.

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, cabochon cutting and faceting, carving, glass beadmaking and craft work. The clubs also promote and facilitate healthy outdoor activities in the form of field trips to various fossicking locations for the purpose of collecting gemstones or mineral specimens. Lapidary is particularly popular in the United States of America and Australia where large numbers of clubs were formed in the 1950s and 1960s.

<span class="mw-page-title-main">Bezel (jewellery)</span> Section on the hoop of a ring

A bezel is a wider and usually thicker section of the hoop of a ring, which may contain a gem or a flat surface. Rings are normally worn to display bezels on the upper or outer side of the finger. In gem-cutting the term bezel is used for those sloping facets of a cut stone that surround the flat table face, which is the large, horizontal facet on the top.

<span class="mw-page-title-main">Diamond (gemstone)</span> Gemstone

Diamond is a gemstone formed by cutting a raw diamond. Diamonds are one of the best-known and most sought-after gems, and they have been used as decorative items since ancient times.

<span class="mw-page-title-main">Hardstone carving</span> Artistic carving of semi-precious stones or gems

Hardstone carving, in art history and archaeology, is the artistic carving of semi-precious stones, such as jade, rock crystal, agate, onyx, jasper, serpentinite, or carnelian, and for objects made in this way. Normally the objects are small, and the category overlaps with both jewellery and sculpture. Hardstone carving is sometimes referred to by the Italian term pietre dure; however, pietra dura is the common term used for stone inlay work, which causes some confusion.

John Sinkankas was a Navy officer and aviator, gemologist, gem carver and gem faceter, author of many books and articles on minerals and gemstones, and a bookseller and bibliographer of rare books.

<span class="mw-page-title-main">Lapidary (text)</span>

A lapidary is a text in verse or prose, often a whole book, that describes the physical properties and metaphysical virtues of precious and semi-precious stones, that is to say, a work on gemology. It was frequently used as a medical textbook since it also comprises practical information about the alleged medical application of each stone. Several lapidaries also provide information about countries or regions where some rocks were thought to originate, and others speculate about the natural forces in control of their formation.

Dopping cement, dopping wax, or faceting wax is a thermal adhesive used by gem cutters to secure ("dop") a gemstone to a wooden or metal holder for grinding and lapping. Setters cement is a similar material used to secure a gemstone while setting or polishing.

References

  1. 1 2 Ripley, George; Dana, Charles A., eds. (1860). "Lapidary". The New American Cyclopædia. Vol. X, Jerusalem–MacFerrin. New York: Appleton. pp. 310–311.
  2. 1 2 Kraus, Pansy D. (1987). "Preface". Introduction To Lapidary . Iola, Wisconsin: Krause Publications. p. ix. ISBN   978-0-8019-7266-9.
  3. "Oxford Dictionaries: Definition of lapidary in English". Oxford University Press. Archived from the original on 22 September 2012.
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  5. 1 2 3 Douglas Harper (2014), Lapidary, Online Etymology Dictionary
  6. William W. Kibler (1995). Medieval France: An Encyclopedia. Routledge. pp. 990–991. ISBN   978-0-8240-4444-2.
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  8. The full and complete history of the lapidary arts International Gem Society, Retrieved January 7, 2015
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  10. Sures Chandra Banerji (1989). A Companion to Sanskrit Literature. Motilal Banarsidass. p. 121. ISBN   978-81-208-0063-2.
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  14. Jason D. Hawkes and Stephanie Wynne-Jones (2015), India in Africa: Trade goods and connections of the late first millennium, L’Afrique Orientale et l’océan Indien: connexions, réseaux d'échanges et globalization, Journal: Afriques, Volume 6 (June 2015), Quote: " The Periplus of the Erythraean Sea, and the Sanskrit Mricchakatika both refer to the jewels made in Ujjain. The evidence from excavations at Ujjain itself, as well as that from surrounding villages, supports this identification. These workshops fed the main market for international trade at the city port of Baruch, at the mouth of the Narmada, which has long been recognized as the main coastal port of the early first millennium. At some point in the mid to late first millennium AD, the center of lapidary workshops appears to have moved from Ujjain to Limudra, and the main port shifted to Khambhat. Exactly when this shift took place and why it occurred is unclear. What is interesting, however, is that throughout the first millennium AD there was a clear and close spatial association between 1) source areas, 2) production centers, and 3) ports connected to the Indian Ocean."
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  22. Davenport, T. (2007-11-27). "Jewels and Jewellers in Pearl". The Review of English Studies. 59 (241): 508–520. doi:10.1093/res/hgm168. ISSN   0034-6551.
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  24. "Mohs Hardness Scale (U.S. National Park Service)". www.nps.gov. Retrieved 2022-02-22.
  25. Rossol, Monona (2001). "Chapter 23: Sculpture, Lapidary, and Modeling Materials". The Artist's Complete Health and Safety Guide. Allworth Press. ISBN   9781581159929.
  26. 1 2 "Dangerous Dust". Rock & Gem. June 22, 2018.