In Jainism, the aasan (seat or mat used during worship, meditation, or scriptural study) should ideally be simple, clean, and pure. Traditionally, white, woolen, or cotton aasans are considered best. The colour white is especially preferred because it symbolizes purity, non-attachment, and non-violence (ahimsa).

Jain scriptures and acharyas often recommend using a white cloth or woolen mat (as wool is considered to have minimal violence compared to silk or leather). Use of bright or dark colours is generally avoided, as they may be associated with attachment or passion (raga).

So, the best colour for aasan in Jainism is white.