An old dark plastic object can prompt an immediate label: Bakelite. The historical story is more useful when it begins with a documented material problem rather than a guess based on colour.
Follow the development question
The Science History Institute’s plastics history links Leo Baekeland’s work to the search for a substitute for shellac as an electrical insulator. It identifies Bakelite’s development in 1907 and discusses its suitability for moulded products.
That account connects material properties with practical uses. It does not mean that every early moulded object is made from the same substance.
Keep the individual object separate
For a museum record, look for the stated material, maker, date and supporting notes. If the material is qualified or uncertain, keep that qualification in your own description.
A photograph can show shape and surface appearance, but it cannot replace a reliable identification. This article does not recommend home tests, heating, solvents or alterations to an object.
Ask a better historical question
Instead of “Is this old plastic important?”, ask how the catalogue connects a material to a particular design or use. That creates a research path you can follow.
For the first descriptive step, see separating appearance from material identification. A careful label keeps an interesting history from being attached to the wrong object.