In Jain dharma, the most uttam fabric for pooja is the one that is clean, simple, modest, and least हिंसात्मक.

In general, for a shravak/shravika:

• White cotton is most commonly preferred.
• Unstitched cloth is considered more proper in many Jain traditions for pooja, darshan, and religious discipline.
• The cloth should be clean, fresh, and sattvik.

About silk:

Your concern is valid. Traditional silk is obtained through harm to silkworms, so from a strict Jain ahimsa standpoint, many Jains avoid silk. Therefore, if one wants to stay closer to Jain principles, silk is not the most uttam choice.

Best choice in Jain spirit:

• Plain white cotton
• Simple, unstitched fabric
• No flashy, luxurious, or attention-seeking cloth
• Cloth that supports humility, purity, and ahimsa

So if you ask, “What is the most uttam fabric?” The answer would be a clean, simple, non-violent fabric like white cotton, not silk.

In Jain dharma, bhav and ahimsa are more important than luxury.