Black Moons are the equivalent to a Blue Moon for New Moons.
Confused? Don't be. Blue Moons are two Full Moons in a month or four in a seasonal cycle. Black Moons are two New Moons in the same vein.
So how can we use these natural cycles in our stories? For supernatural or paranormal subplots? Since I will be working on a werewolf novel next, the mythology surrounding the moon has become late night reading.
I have read about the phases, names, and astrologies of the moon from Celtic to Chinese. The moon as the Earth's only satellite has captured the human imagination for thousands of years. The only avenue left is to create a new mythos for a story that is not complacent, derivative, or juvenile.
When my characters come alive in my head, I bet they will have a lot to say, but for now it's research time. Pass the gmo free bean chips!
Have a great and wonderful day!