When the thumb in Mrigashirsa mudra is held at the base of the Index, middle and ring finger we get the Chatura Hasta.

Following are the instances where Chatura can be used

To indicate lesser quantity
Musk
Gold
Copper
Iron
Dampness
Grief
Aesthetic pleasures
Eyes
Difference in caste
Proof
Sweetness
Slower gait
Breaking into pieces
Face
Oil and ghee