Material is the second level of the collection taxonomy. It identifies the principal material from which an object was made.
Material classification helps visitors understand the physical substance, craftsmanship, technology, and resources behind an object. It can also reveal connections between objects from completely different cultures and periods.
A gold pendant from ancient Colombia and a gold vessel from another part of the world may have very different cultural meanings, but both can be explored through their shared material.
The material category should describe the object's principal or defining material, rather than every substance present in its construction.
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| Materials — An AI-generated vintage watercolor illustration showcasing the diverse natural and crafted materials used to create historical and archaeological objects. |
Material Categories
Porcelain
Porcelain is a fine, highly vitrified ceramic material characterized by a dense body and relatively low porosity.
Porcelain is generally fired at higher temperatures than earthenware and is often associated with thin, refined, and sometimes translucent forms. (Preservation Self-Assessment Program)
Examples include:
porcelain vessels
porcelain plates and cups
porcelain figurines
decorative porcelain
porcelain sculpture
Porcelain is treated as a separate category from the broader Ceramic category because its material characteristics and manufacturing traditions are distinctive.
Ceramic
Ceramic is the broader category for objects made from fired clay or other ceramic compositions that do not require a more specific classification such as porcelain, stoneware, earthenware, or terracotta.
Ceramics can range from practical household vessels to elaborate archaeological objects and sculptures.
Examples include:
ceramic vessels
ceramic decorative objects
ceramic sculpture
archaeological ceramics
specialized ceramic objects
When a more precise material classification is known, the more specific category should normally be preferred.
Stoneware
Stoneware is a durable, high-fired ceramic material with relatively low porosity.
It is generally stronger and less porous than earthenware and occupies a different material category from porcelain. (Preservation Self-Assessment Program)
Examples include:
stoneware vessels
storage jars
tableware
decorative stoneware
studio ceramics
Earthenware
Earthenware refers to relatively porous, lower-fired ceramic material.
It has been used across many cultures for vessels, household objects, architectural materials, and decorative works.
Examples include:
pottery
household vessels
decorated earthenware
archaeological pottery
ceramic figures
Earthenware is particularly useful as a classification for traditional and archaeological pottery that does not meet the more specific definitions of porcelain or stoneware.
Terracotta
Terracotta literally refers to fired clay and is especially useful for objects whose identity is strongly associated with unglazed or naturally colored fired clay.
Examples include:
terracotta figurines
architectural decoration
archaeological figures
terracotta vessels
decorative clay sculpture
Terracotta is technically part of the broader ceramic family, but it deserves its own category because the term is widely used in archaeological and art-historical documentation for distinctive fired-clay objects.
Glass
Glass includes objects made primarily from glass.
Glass has been used to create vessels, ornaments, decorative objects, windows, beads, and many specialized objects across different cultures.
Examples include:
glass vessels
bottles
drinking vessels
glass beads
decorative glass
archaeological glass
stained or colored glass objects
Glass can sometimes be difficult to distinguish visually from other translucent materials. Museum conservation resources note that transparency is often an important clue when distinguishing glass from ceramics and stone, although material identification may require closer examination or scientific analysis. (Preservation Self-Assessment Program)
Bronze
Bronze is a copper-based alloy, traditionally associated primarily with copper and tin.
Bronze has been used for vessels, weapons, sculptures, ritual objects, tools, ornaments, and many other forms of material culture.
Examples include:
bronze vessels
bronze sculptures
bronze ritual objects
bronze tools
bronze weapons
bronze ornaments
Bronze is particularly important in archaeological collections because bronze-working traditions developed independently in many regions of the world.
The material itself can therefore connect objects from very different civilizations without implying that those cultures shared the same artistic tradition.
Brass
Brass is a copper-zinc alloy.
It has been used for decorative objects, vessels, instruments, fittings, household objects, and works of art.
Examples include:
brass vessels
brass ornaments
brass instruments
decorative brasswork
household objects
When an object is specifically documented as brass, it should be classified separately from bronze and copper.
Copper
Copper refers to objects made primarily from copper rather than a copper-based alloy.
Copper has been worked into vessels, ornaments, tools, weapons, decorative objects, and other forms of material culture.
Examples include:
copper vessels
copper ornaments
copper tools
copper plates
copper sculpture
Silver
Silver includes objects made primarily from silver.
Because silver is both visually distinctive and historically important as a precious metal, it has been used for jewelry, ceremonial objects, vessels, coins, religious objects, and luxury goods.
Examples include:
silver jewelry
silver vessels
silver ritual objects
silver coins
silver ornaments
silver tableware
Gold
Gold includes objects made primarily from gold or whose principal visible and structural material is gold.
Gold has been used extensively for jewelry, personal adornment, ceremonial objects, religious objects, vessels, sculpture, and elite regalia.
Examples include:
gold pendants
gold ornaments
gold vessels
gold ceremonial objects
gold sculpture
gold regalia
Gold objects may sometimes contain other metals as alloys.
For example, ancient Colombian objects could be made from tumbaga, a gold-copper alloy, while still presenting a gold-rich surface.
In such cases, the material should follow the most appropriate documented classification for the object's principal material.
Iron
Iron includes objects made primarily from iron.
Iron has been used for tools, weapons, architectural components, household objects, and industrial or technological objects.
Examples include:
iron tools
iron weapons
iron vessels
iron fittings
iron hardware
Iron objects may develop distinctive corrosion products over time, particularly archaeological objects exposed to moisture and other environmental conditions.
Steel
Steel refers to iron-based alloys containing carbon and, in many cases, other alloying elements.
Steel became especially important in later technological and industrial traditions, but historical steel objects can also be found in weapons, tools, instruments, and decorative objects.
Examples include:
steel weapons
steel tools
scientific instruments
architectural components
industrial objects
Steel should be separated from ordinary iron when the object is specifically identified as steel.
Wood
Wood includes objects made primarily from carved, shaped, joined, or otherwise worked wood.
Wood has been used for an enormous range of objects across human history.
Examples include:
wooden sculpture
carved figures
boxes
vessels
household objects
tools
furniture
Furniture should still be classified according to Object Type as Furniture when appropriate, even though its material is Wood.
This illustrates an important distinction:
Object Type tells us what the object is.
Material tells us what it is made from.
Bamboo
Bamboo is treated separately from general Wood because it has distinctive physical properties and has supported specialized craft traditions in many parts of Asia and elsewhere.
Examples include:
bamboo baskets
bamboo containers
bamboo furniture
bamboo carvings
bamboo tools
bamboo decorative objects
Bamboo can be documented separately even when it forms part of a broader plant-fiber or woodcraft tradition.
Jade
Jade includes objects made from jadeite, nephrite, or other materials specifically identified as jade.
Jade has been especially important in the artistic and ritual traditions of East Asia and ancient Mesoamerica, among other regions.
Examples include:
jade pendants
jade carvings
jade ritual objects
jade ornaments
jade figures
jade vessels
Because jade has distinctive cultural and material significance, it is treated separately from the broader Stone category.
Stone
Stone includes objects made primarily from naturally occurring stone or rock that do not fall into a more specific material category such as jade.
Examples include:
stone tools
stone sculptures
stone vessels
architectural stone
carved stone objects
archaeological stone artifacts
Different geological materials may be recorded more precisely in an object's detailed description when known.
The main Material taxonomy, however, can remain at the broader Stone level unless a more specialized classification is necessary.
Shell
Shell includes objects made primarily from natural animal shell.
Shell has been used for jewelry, ornaments, vessels, tools, decorative objects, and ritual items.
Examples include:
shell pendants
shell beads
shell ornaments
shell vessels
carved shell objects
The category can include both marine and freshwater shell unless a more specific distinction is needed.
Mother-of-Pearl
Mother-of-Pearl, also known as nacre, is the iridescent inner layer of certain mollusk shells.
It has been used extensively for decorative surfaces, jewelry, inlay, buttons, boxes, furniture decoration, and luxury objects.
Examples include:
mother-of-pearl inlay
decorative boxes
jewelry
furniture panels
ornamental objects
Mother-of-Pearl is separated from Shell because nacre has a distinctive appearance, material identity, and history of specialized decorative use.
Bone
Bone includes objects carved or constructed primarily from animal bone.
Bone has been used for tools, ornaments, figurines, needles, musical instruments, and decorative objects.
Examples include:
bone tools
bone pendants
bone carvings
bone figurines
bone needles
decorative bone objects
Bone and ivory are related biological materials but should remain separate categories when the source identifies the material.
Ivory
Ivory refers to dense dentine derived from the tusks or teeth of certain animals.
Historically, ivory has been used for carving, sculpture, luxury objects, personal adornment, religious objects, and decorative works.
Examples include:
ivory carvings
ivory figures
ivory pendants
ivory boxes
ivory ornaments
ivory religious objects
Historical ivory objects can originate from different animals, including elephant, mammoth, walrus, and others. The specific source animal should be recorded separately when known.
Paper
Paper includes objects whose principal material is paper.
Examples include:
drawings
prints
paper manuscripts
paper decorations
paper objects
historical documents
Paper may also serve as the support for paintings, prints, or manuscripts. The Object Type and Material classifications can therefore work together.
For example:
Object Type: Paintings & Works on Paper
Material: Paper
Silk
Silk includes objects made primarily from silk fibers.
Silk has historically been used for clothing, textiles, ceremonial garments, embroidery, banners, and luxury fabrics.
Examples include:
silk garments
silk textiles
silk embroidery
silk banners
ceremonial silk objects
Cotton
Cotton includes objects made primarily from cotton fibers.
Examples include:
cotton textiles
clothing
woven fabrics
embroidered cotton
household textiles
Wool
Wool includes textiles and objects made primarily from wool fibers.
Examples include:
wool textiles
carpets
rugs
garments
blankets
woven wool objects
Leather
Leather includes objects made primarily from processed animal hide.
Leather has been used for clothing, bags, footwear, books, armor, household objects, tools, and many other forms of material culture.
Examples include:
leather garments
leather bags
leather bindings
leather footwear
leather tools
leather armor
Lacquer
Lacquer includes objects whose material identity is strongly associated with lacquer construction or lacquer decoration.
Lacquer is traditionally produced from natural resins and has been used to create highly durable and decorative surfaces.
Examples include:
lacquer boxes
lacquer vessels
lacquer trays
lacquer furniture
lacquer sculpture
decorated lacquerware
Lacquer traditions are particularly important in East and Southeast Asian art, although lacquer techniques have been used in other regions as well.
Principal Material
Many historical and archaeological objects are composite objects made from several materials.
A single object might contain:
wood and metal
gold and gemstones
ivory and wood
ceramic and metal
glass and silver
silk and gold thread
lacquer over wood
Museum collections often encounter objects made from several materials, and composite objects can require more complicated documentation and conservation because different materials respond differently to environmental conditions. (Preservation Self-Assessment Program)
For this taxonomy, the Material field should identify the principal material whenever possible.
The supporting materials can be recorded separately in the object's detailed description.
Material Is Not Object Type
Material should never automatically determine the object's Object Type.
The same material can produce completely different kinds of objects.
For example:
Gold
Gold pendant
→ Object Type: Jewelry & Personal Adornment
→ Material: Gold
Gold statue
→ Object Type: Sculptures & Figurines
→ Material: Gold
Gold ritual vessel
→ Object Type: Religious & Ritual Objects
→ Material: Gold
Bronze
Bronze eccentric object
→ Object Type: Tools & Implements or Religious & Ritual Objects, depending on the object
→ Material: Bronze
Bronze sculpture
→ Object Type: Sculptures & Figurines
→ Material: Bronze
Bronze vessel
→ Object Type: Household & Domestic Objects or Religious & Ritual Objects, depending on function
→ Material: Bronze
The material remains the same while the Object Type changes.
Material Hierarchy
Some material categories naturally belong within broader material families.
For example:
Ceramic
Porcelain
Stoneware
Earthenware
Terracotta
These are related but useful as separate classifications because they provide different levels of material specificity. Conservation resources similarly distinguish low-fired ceramics such as earthenware and terracotta from high-fired ceramics such as stoneware and porcelain. (Preservation Self-Assessment Program)
Likewise:
Metal
Bronze
Brass
Copper
Silver
Gold
Iron
Steel
And:
Organic / Biological Materials
Wood
Bamboo
Shell
Mother-of-Pearl
Bone
Ivory
Silk
Cotton
Wool
Leather
The taxonomy can therefore remain easy to browse while still allowing precise classification.
Material and Craftsmanship
Material is not simply a technical label.
It can tell us something about how an object was made and why it looks the way it does.
Stone can be:
chipped
carved
polished
ground
engraved
Metal can be:
cast
hammered
forged
engraved
gilded
inlaid
Ceramics can be:
molded
thrown
hand-built
painted
glazed
Wood can be:
carved
turned
joined
painted
lacquered
Textiles can be:
woven
embroidered
dyed
printed
knitted
felted
The material therefore provides an important gateway into the technology and craftsmanship behind an object.
Material and Cultural Identity
Material can also reveal something about cultural priorities and access to resources.
Gold, jade, ivory, silk, and other valuable materials have often been associated with elite status, ceremonial activity, long-distance trade, or specialized craftsmanship.
At the same time, humble materials can be just as culturally significant.
Clay, wood, stone, shell, and fibers have been used to create ordinary household objects, tools, ritual objects, monuments, and works of extraordinary artistic sophistication.
A material should therefore never be treated as an automatic measure of an object's importance.
A stone tool can be as archaeologically significant as a gold pendant.
A simple ceramic vessel can reveal more about everyday life than an elaborate luxury object.
Material and Conservation
Material classification is also important for understanding preservation.
Different materials respond differently to humidity, temperature, light, handling, pollutants, and other environmental conditions.
Metals may corrode.
Wood and textiles can respond strongly to changes in humidity.
Paper can become brittle.
Glass can suffer from chemical deterioration.
Ceramics can be vulnerable to cracking or breakage.
Composite objects can be particularly challenging because their different materials may respond differently to the same environment. (Preservation Self-Assessment Program)
For this reason, identifying the material of an object is not merely an exercise in cataloging.
It can also be essential for its long-term care.
How Material Works in the Collection
Material answers one fundamental question:
What is this object made of?
It should be considered alongside the other taxonomy levels:
Object Type
→ What is it?
Material
→ What is it made of?
Culture
→ Who made it?
Period
→ When was it made?
Region
→ Where did it originate?
Function
→ What was it used for?
Together, these categories create a multidimensional description of an object.
Examples from the Collection
Maya K'awiil Eccentric Flint
Object Type: Tools & Implements
Material: Stone
Culture: Maya
Period: Late Classic Period
Function: Ceremonial / ritual
The eccentric flint demonstrates why material and function should remain separate. Although it is made from stone and resembles a tool, its elaborate form indicates that it was not simply an everyday cutting implement.
Igbo-Ukwu Shell Vessel with Leopard
Object Type: Religious & Ritual Objects
Material: Bronze
Culture: Igbo-Ukwu
Period: c. 9th–11th century CE
The vessel's elaborate bronze construction demonstrates how material technology can become part of an object's ceremonial and artistic identity.
Tairona Figure Pendant
Object Type: Jewelry & Personal Adornment
Material: Gold
Culture: Tairona
Period: c. 900–1600 CE
The Tairona pendant demonstrates how a precious metal can simultaneously function as a medium for personal adornment, elite identity, and symbolic imagery.
Why Material Matters
A collection becomes much more interesting when objects can be explored not only by culture or historical period, but also by the materials that humans have transformed into art and technology.
A piece of stone can become a tool.
Clay can become a vessel.
Wood can become a sculpture.
Gold can become a tiny figure.
Shell can become an ornament.
Silk can become a ceremonial garment.
Lacquer can transform a simple wooden surface into a highly refined work of art.
Material is therefore more than a label.
It is the physical starting point of the object's story.
Every artifact begins with something from the natural or technological world.
The craftsperson then changes it.
They cut it, carve it, melt it, cast it, weave it, fire it, polish it, paint it, or shape it.
The finished object preserves evidence of that transformation.
Material tells us where the physical story begins.
Aku juga mempertahankan Ceramic sebagai kategori payung sementara Porcelain, Stoneware, Earthenware, dan Terracotta menjadi klasifikasi yang lebih spesifik. Ini paling masuk akal untuk database karena sistem museum memang sering memisahkan kelompok-kelompok tersebut, sementara tetap memperlakukannya sebagai bagian dari dunia keramik. (Preservation Self-Assessment Program)