I am a daughter of the Moon. As such, I am into all things Moon. This is something that needs to be clarified.
A Dark Moon describes the Moon during that time that it is invisible against the backdrop of the Sun in the sky. The duration of a dark moon is between 1.5 and 3.5 days, depending on the orientation of the Earth and Sun.
In astronomical usage, the New Moon occurs in the MIDDLE of this period, when the Moon and Sun are in conjunction.
Astrologically and magickally, the Dark Moon (Crone time) refers to the period when the Moon is not illuminated in any way, like it is currently (3/27/17 1:11pm USA), it is the period between the end of the Waning Moon and the start of the Waxing Moon.
Astronomically, the New Moon (Maiden time) refers to the midpoint of the Dark Moon, the time of which the Moon is exactly between the Waxing and Waning phases.
Astrologically and magickally, this refers to the very beginning of the Waxing Moon, when the Moon is again illuminated by the Sun; that very first Crescent of Moon in the Sky.
Many people these days refer to the Dark Moon as the New Moon. I prefer to use ancient astronomical definition. This way is more intrinsic to nature. During the Dark Moon, magick that is practiced is of the ridding, or banishing type. Typically when the Dark Moon is in alignment with Earth I use this energy to rid myself of unwanted thoughts, behaviors, and processes in an effort to ready myself for the New Moon that will appear approx two days after the Dark Moon. This Moon is the perfect time to practice Divination that will lend insight and illumination into what you should consider in preparing for the New Moon ahead. When it is indeed a New Moon, when the first tiny sliver of moonlight is shed, I perform magick that is in-line with newness, rebirth, and renewal.
What do you need to banish from your life right now under this Dark Moon? Poor health, financial challenges, obstacles of any kind? Now, under the Dark Moon, this Crone Moon, is the time to do away with the things and people that no longer serve you and are standing in the way of you totally realizing yourself. Prepare yourself for newness. Banish now under the Dark Moon, plant seeds of hope and promise under the true New Moon.