This is a miniature bronze altar to Hecate for use in magic. It is from Pergamon (Pergamum) in Asia Minor, now Turkey, and dates to around 200-50 CE. You can see the real thing in the Staatliche Museen in Berlin. I happen to have been to Pergamon in the last 6 months, so I'll include some images from there as well. Pergamon is a Hellenistic hilltop city which had probably the steepest theatre in the entire ancient world, you can see it here, embedded into the hillside - talk about vertigo! The second shot is taken from standing at the top of the theatre, looking down - you wouldn't want to be drunk whilst watching a play, you'd fall straight down. The next pic is a temple of the Imperial Cult on the top of the Pergamon citadel. Books were also invented in Pergamon, they couldn't get papyrus for some reason, so had to make pages out of vellum and this turned into what we know of as the book - they used to read scrolls before that you see.