But I'm starting with a pretty easy one, no prizes for this one, I know what this is. I'll give clues if you ask!
Also, I apologize for my photography skills. I badly need a tripod.
This object is made of boxwood. It's polished smooth but not varnished, and is quite tightly sprung - it's not overly difficult to press open but requires a conscious effort to keep it that way. It's about a centimetre thick all along the length - I'm sorry I forgot to take a photo of it widthways. Other than that, very simply made.