Coro brooch

Hello to everyone! this is the very first item I bought in a fair and made me fall deeply in love with costume jewelry. I love this brooch very much, even though I was looking for a maltese cross... but I have no idea what those symbols at the front mean. Also, I've had troubles dating the item, since the italic written "Coro" has usually not that kind of "r".... could you help me please? oh, I have not found any patent or advertising for this one.
I' m just a beginner and I'd love some help and advice on books and stuff like that... thank you very much!