A kartika is a small, symbolic crescent knife or 'chopper', used in Vajrayana

Vajrayana

Vajrayāna Buddhism is also known as Tantric Buddhism, Tantrayāna, Mantrayāna, Secret Mantra, Esoteric Buddhism and the Diamond Vehicle...

 Buddhist ceremonies. It symbolizes the severance of all material and worldly bonds and is crowned with a vajra

Vajra

Vajra is a Sanskrit word meaning both thunderbolt and diamond...

, which is said to destroy ignorance, and leads to enlightenment. The kartika is a key ritual

Ritual

A ritual is a set of actions, performed mainly for their symbolic value. It may be prescribed by a religion or by the traditions of a community. The term usually excludes actions which are arbitrarily chosen by the performers....

 implement in the Tibetan Buddhist practice of Chöd

Chöd

Chöd , is a spiritual practice found primarily in Tibetan Buddhism. Also known as "Cutting Through the Ego," the practice is based on the Prajñāpāramitā sutra...

, or 'cutting through demons'. In Buddhist teachings, this tool is held in the right hand of Yama

Yama (Buddhism and Chinese mythology)

Yama the name of the Buddhist dharmapala and judge of the dead, who presides over the Buddhist Narakas , "Hells" or "Purgatories". Although ultimately based on the god Yama of the Hindu Vedas, the Buddhist Yama has developed different myths and different functions from the Hindu deity...

, the conqueror of death. It is also used in Feng Shui

Feng shui

Feng shui ' is a Chinese system of geomancy believed to use the laws of both Heaven and Earth to help one improve life by receiving positive qi. The original designation for the discipline is Kan Yu ....

.

Depictions of Vajrayogini typically contain the kartika as one of her attributes. In the iconography of the dakini

Dakini

A dakini is a tantric deity described as a female embodiment of enlightened energy. In the Tibetan language, dakini is rendered khandroma which means 'she who traverses the sky' or 'she who moves in space'. Sometimes the term is translated poetically as 'sky dancer' or 'sky walker'. The dakini, in...

, she generally appears with the hooked kartika knife in her right hand. Tsultrim Allione

Tsultrim Allione

Lama Tsultrim Allione is an author and teacher who has studied in the Tibetan Buddhist lineage. She was born in 1947 in Maine, in the United States, and given the name Joan Rousmanière Ewing. She first travelled to India and Nepal in 1967, returned in 1969 and in 1970 she became one of the first...

 describes the kartika:

The traditional interpretation of the hook in Tibetan Buddhist imagery is that of the hook of compassion. It is the hook which pulls beings out of the cycles of transmigration. The hooked crescent-shaped knife of the dakini with its vajra handle pulls one forth from suffering, chops up the ego-centred self and is guided by the diamond clarity of the vajra.

The kartika usually appears as a pair with the kapala

Kapala

A kapala or skullcup is a cup made from a human skull used as a ritual implement in both Hindu Tantra and Buddhist Tantra...

, or skullcup.