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Primo: using the library catalogue: Classification scheme

Library of Congress

Once you've found the item in Primo, you will then need to visit the shelves to retrieve and borrow it!

Aberystwyth University libraries use the Library of Congress Classification system to arrange books on similar subjects together.

It is a series of letters and numbers arranged in particular ways, starting with major categories and breaking them down further into subcategories. This page will give you an overview of how books are shelved in the libraries, how to successfully read classmarks and how to find the book you want on the shelves. 

Subjects outline and locations

Library of Congress Classification, Main Subject Classes:

A: General Works  
B: Philosophy, Psychology, Religion  
C: Auxiliary Sciences of History, such as
Archeology,Genealogy, Biography
D: World History, including history of
Europe, Asia, Africa, Australia, New Zealand
E-F: History of the Americas
G: Geography, Anthropology, Recreation  
H: Social Sciences
J:  Political Science
K: Law  
L: Education
M: Music  
N: Fine Arts 
P: Language and Literature  
Q: Science  
R: Medicine  
S: Agriculture  
T: Technology  
U: Military Science  
V: Naval Science  
Z: Bibliography, Library Science,
  Information Resources

Further information

Finding the book you want in the library

To find a book in the library you will need its classmark - every item in the library has its own unique classmark. The library uses the Library of Congress classification scheme to sort out where the books are to be located on the shelves.

You will see classmarks on the spines of books... 

and in the library catalogue Primo, when you search for the item online. 

 

Note that the same classmark can be written and read from top-to-bottom (e.g. spine of book) or left-to-right (on Primo).
  • Each book has a unique classmark composed of letters and numbers, which is used to determine the book's placement on the shelf, and to group it among other books on the same subject,
  • On the end of each bay of books, you will see signs stating what classmarks can be found there and a brief description of the subject area.

  • Journals are shelved alphabetically by title.

After searching Primo you will need to convert the classmark from the online catalogue display to a vertical form (as it appears on the spine of a book):

Example: 

Read it as...

QK

306

.S9

as it would appear on the spine of the book. 

First Line: 

The first letter or set of letters is alphabetical. A comes before B comes before C, and R comes before RA comes before RB. Single letters are filed before double letters in terms of shelf arrangement.  For example, this series is in the correct order:  D   DA   DF   DL    DT

The first letter indicates a very broad subject area, which is made more specific by adding a second and sometimes third letter.  For he example above...

Q = Science

QA = Mathematics

QH = Natural history - Biology

QK = Botany

From the example given above, QK306...we now know that the QK classmark relates to botany. 

Second Line: 

Next comes a set of numbers in numerical order. 5 comes before 50 comes before 500. This line is read as a whole number. Numbers on the second line can range from 1 to 9999 and can also have decimal points.

Example: 32 (thirty-two) is shelved before 310 (Three hundred ten).  Any number followed by a decimal point is filed decimally.
Example:  8701 is shelved after 8700.7          8700.7 is shelved after 8700.17


Third Line: 

The third line is a combination where you read the letter alphabetically first then the number as a decimal. This line begins with a decimal point, followed by a letter and number sequence.  The letter is alphabetical, as above.  The numbers here, however, are in decimal order rather than numerical order.  For example B69 above would come after B6 but before B7 or B695.  Just take it one number at a time and remember here that the letters are read alphabetically and the number is read as a decimal.

Example: .P266 comes before .P87

There you go!  That’s how to read Library of Congress classmarks.  Next, go to the shelves and look for the book by reading the classmark line by line. 

You may come across classmarks with additional lines to read.

Examples:

CELT

The Celtic Collection brings together material relating to Brittany, Cornwall, the Isle of Man, Ireland, Scotland and Wales, and contains approximately 25,000 books. Although the collection contains material on all subjects relating to Celtic countries, the two largest sequences are those on history and literature.

The collection is housed on Level F of the Hugh Owen Library. Most items in the collection have the prefix CELT on the spine, with the exception of classes DA (History) and PB (Language and literature) and all may be found on Primo.

 

FOLIO (FOL)

FOL at the end of a classmark means that the book is too big to fit on normal shelves and is called a Folio.

These go in a separate section with bigger shelves.

 

DICTIONARY (DICT)

A separate dictionary collection is available on Level F and have a prefix DICT on the spine.

 

Effective Study Collection (STUDY)

The Effective Study Collection is a collection of books designed to help you study. It covers such topics as how to research and study, writing skills, academic writing, English usage, time management, communications skills and some general guides to research and study in the arts. The material is intended for all users, including those for whom English is not their first language. All items in the Effective Study Collection are added to the Library catalogue, Primo, and have the prefix STUDY in the classmark. Effective Study Collections are located on Level F of the Hugh Owen Library and in the Physical Sciences Library. 

Pamphlets (PAM)

For Aberystwyth University Library purposes a pamphlet is usually considered to be a publication of less than 50 pages with limp covers.

Pamphlets have the suffix 'Pam' or 'Pam Qto' added to the classmark e.g. HD6664.G7 Pam and are shelved in pamphlet boxes at the start of each classification i.e. HD pamphlets are shelved before HD books.

Quarto (QTO)

Qto at the end of a classmark means that the book is bigger than normal, and stands for Quarto.

  • In Hugh Owen Library the Quartos are shelved in the main sequence of books.
  • In the Physical Sciences Library the Quartos are separated from the rest of the books due to shelf size.

  • Check the item is available to borrow in Primo
  • Write down the classmark or have the Primo record available on your mobile device
    • One wrong number or decimal point and you'll end up with a completely different book. 
  • Check the classmark carefully - make a note if it has CELT, STUDY, DICT or Pam etc.  
  • Check what floor the book is located on in the Hugh Owen Library - Level E or Level F
  • Check which library the book is located - Hugh Owen Library or Physical Sciences Library
  • Break the classmark down line by line when you reach the shelf
  • You can get a general idea of which shelves to start searching by the guide numbers displayed on the end of each bay
  • As books are organised according to subject, you can use classmarks to see where to start browsing the shelves. You may find another book on the same subject that may be of interest to you just by browsing what's located nearby

You may find a book that Primo states as 'Available' but you cannot find it on the shelf. There could be a number of reasons for this:

  • A user might have retrieved it from the shelf to use in the library but not issued it to themselves
  • The book may have been newly returned and awaiting to be re-shelved at its correct location. These books will be placed on 'Rough Shelving' or can be found on the floorplans as 'Items for shelving'. These are designated shelves on Level E and Level F where newly returned items awaiting to be put back on the shelves are placed. The books on these shelves are grouped by the first letters of the classmark and are not in classmark order - they are randomly placed on these shelves.
Level E rough shelving

 

Level F rough shelving

  • If still not found, the item may have been mis-shelved or is missing.
  • In this case, visit the Enquiry Desk and the Librarian will report it and procedures are in place to try and locate the item. You will be informed by email of any updates regarding the item.  
  • If you're having trouble finding your book or need help with classmarks, you can always go to the Enquiry Desk on Level F or Level D and ask for assistance from a member of staff.  
  • You can contact your Subject Librarian for advice.
  • You can also contact library staff via chat, text, or email:

 

Need help? Just ask!