Mud bullock's new moon day

Mud bullock's new moon day (मृद्वृषभ अमावास्या / ಮಣ್ಣೆತ್ತಿನ ಅಮವಾಸ್ಯ)

ಜ್ಯೇಷ್ಠ-ಅಮವಾಸ್ಯ

ज्येष्ठ-अमावास्या

Jyestha-New moon day

On this day, two bullocks must be made out of mud, Taurus (वृषभ / ವೃಷಭ) must be invoked in them and worshipped in 16 ways as described in the shaastraas. The shaastraas command us to worship mud idols for five times in a year, and this one among them.

More details can be found at http://sampada.net/blog/brahmana/12/09/2008/11695