British Museum Materials Thesaurus


Editor's preface
Structure and content of the thesaurus
Sources consulted
Alphabeticallist with links:
A,B, C,D, E,F, G,H, I,J, K,L, M,N, O,P, Q,R, S,T, U,V, W,X, Y,Z
Index of terms:
A, B,C, D,E, F,G, H,I, J,K, L,M, N,O, P,Q, R,S, T,U, V,W, X,Y, Z
Note on This Version

Editor's preface

The decision to publish The British Museum materials thesaurus was based onthe interest shown in it over the years by visiting documentation specialists,and their requests for copies. In my opinion, the thesaurus is unique, due tothe great range of terms included, the inevitable consequence of documentingworld-wide collections from almost any historical period, a great variety ofcultures, and covering almost any type of object. The eclectic nature of thelisting precluded the possibility of importing a thesaurus into ourdocumentation system, and we therefore had to devise our own version. Thegreatest difficulty lay in providing an overall structure which couldaccommodate specialised terminology, archaic or local names for certainmaterials, and everyday nomenclature as well. Our thesaurus indicates oneapproach, no doubt there are many others (indeed we tried several beforesettling on the current structure). I am reassured by the fact that our usersregularly retrieve records by material, using the thesaurus as a retrieval tool.

I would be very grateful to receive comments and suggestions, but stressthat we did not attempt to cover all materials from which objects can be made,and that we intended to produce a pragmatic, rather than a scientific,thesaurus. It is strictly based on The British Museum's documentation of itscollections, and will be regularly updated as new terms are added at data entry,or as a result of research by curatorial, scientific or conservation staff.

Tanya Szrajber
Department of Scientific Research
TheBritish Museum
August 1997

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A thesaurus is a hierarchical list of terms, which may be inter-related andoften have explanatory notes called Scope Notes. Thesauri are used tostandardise terminology, thereby achieving consistency in data entry andfacilitating retrieval. The British Museum's collections documentation projecthas established several thesauri, and the following abbreviations define thestatus and relationships of the terms.

PT: Preferred Term - a term is a PT by default, and the user isrecommended to use it.

NP: Non-Preferred Term - the user is advised not to enter the term,but to use the associated PT instead.

BT: Broad Term - a term encompassing one or several terms beneath itin the hierarchy.

NT: Narrow Term - a term placed under a higher level term in thehierarchy.

RT: Related Term - a term comparable to other terms in thethesaurus, which may be a useful alternative for retrieval.

TT: Top Term - a term at the highest possible level in thehierarchy, provided primarily for classificatory purposes; such a term shouldrarely be used in data entry.

TE: Temporary Term - a term awaiting discussion by the Working Partyfor possible incorporation into the thesaurus.

Scope Note - an explanatory note accompanying a term.

The Materials thesaurus was initially compiled from index terms generatedfrom computer records created using curatorial documentation and the objectsthemselves. A Working Party was set up with representatives from the CollectionsData Management Section (CDMS) associated with various curatorial departments.Terms were vetted, incorporated into an overall hierarchical structure, andother thesaural relationships and features added. Curatorial and Conservationstaff were consulted over problematic or ambiguous entries, and the final listswere checked by colleagues in the Department of Scientific Research. It isstressed that the final listing is not intended as a scientific classificationsystem, rather it is a reflection of the terminology, both current andhistorical, in use in curatorial departments in The British Museum. As with allBritish Museum thesauri, Temporary Terms can be set up at data entry, to bediscussed by the Working Party and if suitable, added to the thesaurus. ScopeNotes are provided to explain the meaning of the more obscure entries or torestrict usage to a particular context or department. The terms are in thesingular form, and hyphens are avoided, unless they reflect standard spelling.Foreign words are included, although higher-level terms are in English.

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Structure and content of the thesaurus

Three Top Terms are provided - 'Organic', 'Inorganic' and 'ProcessedMaterial' and are generally mutually exclusive. 'Organic' is definedas naturally occurring animal and plant material, and naturally occurringsubstances derived from them. 'Inorganic' is defined as naturallyoccurring material which, for the purposes of this thesaurus, is not of organicorigin, i.e. mainly minerals and stones. 'Processed material' may beregarded as material which has been manufactured or has undergone some form ofprocessing (such as smelting) to alter it from its original natural state. Thedefinitions of the three categories are provided for general guidance, ratherthan as strict formulations. It is accepted that there are grey areas,particularly in deciding whether a substance is processed or not. However theprimary intention is to group materials in a way which is meaningful to theaverage user.

The following structure shows the main categories.

silver chloride
silver nitrate

It was decided that for the sake of simplicity, materials in the 'ProcessedMaterial' category would not be placed under more than one Top Term. The onlyexceptions occur for certain textile terms which refer to the cloth and theprimary material, such as 'cotton'.

A category 'Unknown' has also been created to cover instances where thematerial is genuinely unidentified and requires analysis. The Material fieldshould be left blank if the material has been omitted from the documentation.

The Materials thesaurus should be used in conjunction with the Object Namesthesaurus for certain terms which might conceivably fall under either category,For example terms such as 'dye' or 'paint' are regarded as Object Names (underthe Broad Term 'sample') and their constituents (such as 'urucu') as materials.


The main categories are animal and vegetal materials which have beenarranged primarily by constituents such as 'bone' or 'wood', reflecting the mostcommon types of retrieval requests. As shown in the accompanying diagrams (Fig. 1 and Fig. 2)these are then subdivided into named examples, such as 'mammal bone' or 'pearwood'. There is no attempt to provide taxonomic classifications of animals andplants, although some form of grouping does occur.

The thesaurus allows for two types of search. The user can retrieve recordsrelating to a particular animal or plant by searches for terms beginning withthe specific name (e.g. 'tiger' or 'areca palm'). Alternatively, the user canretrieve according to constituent by making use of the Broad Terms (e.g. 'seed'or 'claw') regardless of the particular animal or plant.

The 'animal' and 'vegetal' sections also incorporate terms for materialsextracted from plants or produced by animals, under the Broad Terms 'plantextract' or 'animal product'.

The 'Organic' category also includes the hydrocarbons (e.g. asphalt,bitumen, coal, jet, pitch and tar) which are defined in this thesaurus asnaturally-occurring although they may in some classification systems be regardedas processed. Other materials of particular interest are the so-called 'organicgem materials' which occur in various sections of the 'Organic' category andinclude amber, copal, coral, jet, mother-of-pearl, pearl, shell and vegetableivory.


The first level of Broad Terms is a list of constituents (e.g. 'hoof' or'bone') including 'animal tissue' which, like its Narrow Terms, does not referto 'tissue' in a strict biological sense. It is a necessary inclusion forinstances in which a combination of constituents (e.g. 'donkey leg'),unspecified matter from a named animal, or even the whole animal name (e.g.'catfish') have been used in the documentation.

Further down the hierarchy the names of specific animals (e.g. 'parrotfeather') or groups (e.g. 'mammal claw') are incorporated. The level ofspecificity reflects the documentation, which may record 'mammal bone' in someinstances, or 'arctic fox bone' in others. For this reason, certain intermediaryBroad Terms which might be expected are not included (even though comparableterms are present). Thus, for example, 'marsupial fur', 'marsupial bone', etc.are listed, but 'marsupial claw' is not (and 'kangaroo claw' therefore has BT'mammal claw'). As stated, the thesaurus does not reflect an attempt to providea rigorous classification system, but rather to incorporate data used in theBritish Museum records.

The category 'animal product' comprises materials produced by animals (e.g.'ambergris' or 'beeswax') as opposed to materials extracted from them (such as'animal oil' or 'animal fat').


The first level of includes a list of constituents (such as 'seed' or'fibre'), the specific term 'charcoal', and the two Broad Terms 'plant extract'(with Narrow Terms such as 'indigo' or 'henna') and 'plant specimen'. The latterfunctions in a similar way to 'tissue' in the animal hierarchy, as it is a BroadTerm for named specimens such as 'acacia' (which could refer to unspecifiedparts or the entire plant), although it can also be entered as a Preferred Termfor un-named specimens. Further down the hierarchy, the names of specific plantsor groups, are included, as with the animal section (e.g. 'cucumber seed' or'palm leaf'). No attempt has been made to provide a classification of terms inthe 'Vegetal' section, such as 'monocotyledon leaf' or 'hardwood', since suchterms have not been used in the records.

In a small number of cases, the constituent is not actually named, butrather is implied. After some deliberation, it was decided that if a termnaturally suggested a constituent in everyday language, it was unnecessary tospecify it. Thus, for example, it is assumed that 'willow' refers to the wood(and therefore has the Broad Term 'wood') but other references have to be fullyspecified (e.g. 'willow bark'). The same argument applies to various kinds offruit or flower. Since 'rose' implies the flower, and 'peach' the fruit, etc.,it is unnecessary to specify 'rose flower' or 'peach fruit', which would beclumsy terms in everyday usage.


This category comprises mainly minerals and stones. Minerals are looselydefined as naturally occurring chemical compounds of non-biological origin.Since minerals have a 'chemical' name as well as a 'mineral' name, either ofwhich may have been used in the documentation, both versions will be Preferred,with the 'chemical' name as the Broad Term). As mentioned above, it was decidedto place 'organic gem materials' in the Organic section of the thesaurus.

Stones are loosely defined as combinations of minerals. The term 'stone' isalso the material which should be entered in the case of fossils, and 'fossil'retained as an Object Name. This category (and the one below) also include'lime' because it has been used to cover several substances in thedocumentation, which can only be distinguished through future analysis.


This essentially comprises man-made materials (e.g. 'rayon') and otherswhich have been altered in some way from their natural state (e.g. 'pottery').It is impossible to define how much or what kind of processing is necessarybefore a material is placed in this part of the thesaurus, and common sense isthe ultimate guide. The presence of some categories may not be immediatelyobvious to the average user, as in the case of 'metal', which is includedbecause in most cases it has undergone extraction and smelting before beingused. The term 'synthetic' is a Broad Term for all plastics, and should also beentered as the material for objects which are described as being made of'synthetic wool' or 'synthetic caribou sinew', for example, in the absence of amore specific information. An important category in this section is 'textile',which covers any cloth, whether woven, knitted, beaten, or otherwisemanufactured. Where the primary material of the textile is definitelyestablished for all cases, the link has been made in the thesaurus by aproviding a second Broad Term (e.g. 'calico' has BT: 'cotton' and 'textile').Where the primary material may vary, the connection has to be made in eachindividual record by multiple keywords:


The term 'textile' should also be entered as an additional keyword ininstances where materials which are not Narrow Terms of 'textile' havenevertheless been used in this context. An example might be a garment made ofwoven palm leaf, which would have the following entries in the Materials field:

e.g.[palm leaf]

CDMS (Materials Working Party)
Department of Scientific Research
TheBritish Museum

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Sources consulted

Allaby, M. (ed.). The Concise Oxford Dictionary of Botany,Oxford, 1992.

Clutton-Brock, J. A. Natural History of Domesticated Mammals,Cambridge University Press and British Museum (Natural History), 1987.

J. Paul Getty Trust. Art & Architecture Thesaurus,Oxford University Press, New York, 1994 edition.

Hodges, H. Artifacts - An introduction to early materials andtechnology, London, 1964.

Royal Commission on the Historical Monuments of England. Thesaurusof Building Materials, [unpublished], 1996.

Whitten, D. G. A. with Brooks, J. R. V. A Dictionary of Geology,Penguin Books, 1972.

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Current CDMS Working Party (1995-7): Sandor Burslem, Amanda Gregory.

Chair: Tanya Szrajber.

Previous Working Party members: David Bellamy, Fiona Cameron, SimonCohn, David Collens, Michael Downing, Siobhan Flynn-Collins, Lucy Glazebrook,Daniel Groves, Lea Jones, Bridget Stensel.

Figures by Sandor Burslem and Amanda Gregory.

With special thanks to:
Dr Sheridan Bowman, Dr Caroline Cartwright, DrPaul Craddock, Dr Ian Freestone, Ms Sylvia Humphrey, Dr Andrew Middleton, MrDavid McCutcheon, Mrs Susan La Niece, Ms Allyson Rae, Ms Yvonne Shashoua, AntonySimpson, James Tullett and departmental curators.

Web version prepared by Gordon McKenna of

Note on This Version

Within this version of the thesaurus the use of an '' indicates an hypertextlink to another term

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© Trustees of The British Museum, 1997.
Youmay freely download this page for non-profit use, but must acknowledge theTrustees in any output in which it is used.
The Trustees acknowledge thework of in converting thisresource for use on the Web.