This is a Victorian paper mache ink well tray/holder with mother of pearl. It has the ink well, it is missing the lid for it.
Paper mache products were popular during the Victorian years. The process to create these items was a long one involving many iterations of layering the material and baking and repeating. After baking in intense heat, the product became durable.
This one is the traditional black with sparkles of mother of pearl. I can imagine it placed on a Victorian desk with ink pen resting in the trough in wait of use. Then a lady in full day dress sits at the desk, dips the pen in ink and dashes off a note.
It is amazing to have this connection to our ancestors.