Ramayana
अर्जुनस्य गदा सा तु पात्यमाना ऽहितोरसि । काञ्चनाभं नभश्चक्रे विद्युत्सौदामिनी यथा ॥ 7-32-56 ॥
And that mace of Arjuna's, as it was hurled down upon the foe's chest, made the sky shine with a golden hue, like a flash of lightning.
english translation