The image of the Mother as eternal giver of life was one of the first religious images that can be found. Before patriarchal gods appeared, the Goddess was revered in her aspect as Creatrix.
Studying compared religions we can find the true extension of Her worship, and this is, by far, Her most vastly known image. This is the aspect all figurines from the neolithic call upon, like the famous Venus of Wildendorf. Their common characteristics are those indicating maternity or pregnancy: swollen belly and prominent breasts and sex, all of those suggesting they're related to fertility cults.
There are many examples available of this aspect of the Goddess, that can be traced back to different cultures.
Among the Greeks, in charge of Earth's fertility and harvests. She's closely related to Persephone or Proserpina, an aspect of the Maiden
whose worship predates greek Olympic mythology, represented Earth, and was the one that gave birth to the Titans. As a curious note, nowadays Earth receives her name again, in the theory that sees earth as a whole being.
to the Egyptian's, also called the Great Mother Creatrix and Giver of Life, and associated to the Moon. It's well documented the mythological relation between Her and the floods of the Nile, that commanded the agricultural life of the people.
In Ireland, the Mother of a Trinity among Anu and Macha, possessed a magick cauldron as a symbol of the primeval womb, and was also renown for her accurate prophecies.
In Norse mythology, considered the leader of the Disir, the Divine Matriarch. Intimately related to magick, she had the ability to fly, and two cats, Bygul and Trjegul, pulled her carriage.
Mother Earth for the Inca, is still revered in syncretic rituals with christian influences. We could say She's the most widely known image of the Mother in Latin America.
In some of the usual mythological images of the Mother we can appreciate both creative and destructive attributes. This we could see as an attempt to represent Mother Nature in all her aspects. As we hinted in the previous point, the Maiden, many a time different aspects of the Goddess relate and intertwine, making it a bit difficult to fully identify each of Her phases on it's own.
There is a supposition that many of the myths we mentioned before have reached us already corrupted by the conquests the cultures which originated these myths, primary matriarchal, suffered. There are even some alternative versions of some of them, pretending to reconstruct the original cycle, but sadly this is something we'll never know for certain.
The Mother can be identified with the Full Moon, being the patroness of the harvests and watching over women's and animal's fertility, and nature's in general. Her special festival is Brigantia. The colour for Her is red, and Her animals are the cat, dove or dolphin.
We should call this aspect of the Goddess when we want to deal with things related with motherhood, protection (especially when we're dealing with women threatened by men), marriage, guidance, achievement of inner peace, choices of any kind, spiritual development and intuition and psychic gifts.