Austria 1886-1922. What are the other marks?

[Mjl]

I'm not sure what this item is?! I suspect it was once meant to have a glass bowl? The Diana head mark indicates Austria-Hungary 1886-1922, and I think the letter is A - Vienna. The other mark is RO? Indicating Rudolf Oswald? Any thoughts or suggestions on the marks, or what the item is would be great!