A catalogue has one entry for a box, but the photograph shows a base and a separate lid. Counting entries and counting physical pieces would produce different totals, and both counts need labels.
Name the thing being counted
In a fictional collection exercise, write “one catalogue entry, two observed components”. Do not assume that the institution uses your component description as its own formal numbering system.
If the record supplies part identifiers, copy them accurately. If it does not, use clearly marked descriptive labels in your personal notes.
Connect each observation to a component
A scratch on the lid and a mark on the base should not merge into a vague statement that the object is marked. State which part is visible and where the observation belongs.
When working only from photographs, do not infer that an unseen underside has no marks. It is simply outside the available view.
Keep association separate from certainty
A photograph showing pieces together does not by itself explain when or how they became associated. Look for the catalogue’s description of the relationship and retain any uncertainty it records.
Use careful catalogue reading as the next step. A clear component count helps prevent small recordkeeping choices from turning into larger historical assumptions.