Athena in full armour. Notice the Aegis, goat skin armour - with the gorgons head in the centre. You'll find that she almost always wear it in ancient art.
An Etruskan antefix (terracotta), decorated with a gorgon. Athena normally appear in art with the gorgon adorned aeigis (goat skin armour).
"Meanwhile Minerva flung her richly embroidered vesture, made with her own hands, on to her father's threshold, and donned the shirt of Jove, arming herself for battle. She threw her tasselled aegis about her shoulders, wreathed round with Rout as with a fringe, and on it were Strife, and Strength, and Panic whose blood runs cold; moreover there was the head of the dread monster Gorgon, grim and awful to behold, portent of aegis-bearing Jove. On her head she set her helmet of gold, with four plumes, and coming to a peak both in front and behind- decked with the emblems of a hundred cities; then she stepped into her flaming chariot and grasped the spear, so stout and sturdy and strong, with which she quells the ranks of heroes who have displeased her. Juno lashed the horses on, and the gates of heaven bellowed as they flew open of their own accord"
Homer - The Iliad II
translated by S.Butler