Guide to Object Marks
There are many reasons why an object in a museum may have been marked with numbers and/or letters and objects may bear several different markings. They might refer to the registration (accession) number, another sort of museum label (e.g. an object date/period in Roman numerals), a collector's number, an auction lot number, a previous museum number or they might be a reference to a field site and a particular year of excavation.
Each excavation season produced different habits and methods of marking. For Egyptian archaeology, Flinders Petrie described his system of marking objects in detail in the introduction to his publication Naqada and Ballas published in 1896. His processing of finds followed several distinct stages:
(1) A find-group (in a cemetery, a burial) was located and cleared of soil by a skilled trained Egyptian excavator; then
(2) A Western supervisor would mark each object from the find in pencil, to avoid confusion with objects from other finds.
(3) The marks would be over-written in ink when brought from the find-place to the excavation house.
For some seasons the object marks are distinctive. For others, there is a lot of confusion because the same system was employed in different places meaning, for example, that there were several 'cemetery B' artefacts, marked with a number and a letter that could be from several different seasons.
There are three main types of object marks:
Year-Date and Context number
These labels are the most straightforward for interpretation and were in use on excavations from the 1920s and 1930s. The directors of those excavations employed variants of 2-part numbering systems for finds:
(i) For excavations of cemetery and settlement sites such as Sidmant (1921-1922), Abydos (1922) and the series of sites from Qau and Badari to Matmar and Mostagedda (1922-1928) excavated for the British School of Archaeology in Egypt (BSAE), each object is identified by the year (without the 19) and find-context (a number between 1 and 10,000s). Often, round numbers are used for general contexts; so “300” means “cemetery 300” (no precise location within cemetery 300) whereas “301” means tomb 301 (= tomb 1 in cemetery 300). Sometimes they are written as a fraction e.g. 23/620 for Qau season 1923 tomb 620 (tomb 20 in cemetery 600) or the year is in smaller letters set superscript to the context number e.g 22330 for 1922 tomb 330.
(ii) for the site of Amarna (also known in Egyptology as Tell el Amarna), in the 1920s-1930s excavations funded by the Egypt Exploration Society, each object is identified by 1. site name, abbreviated as TA, 2. date of excavation (without the 19), 3. number in a series of finds. These objects usually also bear a mark giving location on the grid used for the site since the 1910s.
Letter and Number
From about 1894 onwards, Flinders Petrie designated different areas with a series of letters. Unfortunately this was repeated at many sites. Sometimes by cross-checking the handwriting with other collections and looking at the number itself (e.g. if a particular cemetery even goes up to say B823) can narrow down the possibilities. For instance, the form of the letters used for cemetery
Objects with numbers of uncertain date
Sometimes an excavator simply placed a number onto an artefact, which might refer to a specific tomb, deposit or settlement area. Roman numerals were often used to indicate Egyptian dynasty (e.g. XVIII would be Dynasty 18 of the New Kingdom). Again cross-checking this website will hopefully narrow down the possibilities.