Handwritten ink marks appeared on oracle bones and jade as early as the Yin and Shang Dynasties. Although there were occasional discoveries after that, the number was too small and scattered to constitute a complete calligraphy style. It could only reveal some early information about pen and ink, so it was subordinate to the oracle bone gold calligraphy at that time. But by the late Spring and Autumn Period, handwriting and ink had begun to be used on a large scale. By the Warring States Period, handwriting became increasingly common and gradually became the dominant form of calligraphy in this era.