A right-turning, white conch is sacred to Buddhists as one of the eight auspicious symbols. It represents the sound of the Dharma, the teachings of the Buddha. My second guess would be something used in ritual to pour liquid through and one person on other side to drink it
Context is everything you'll have to give a little bit more information about the area it was found.
As far as it being a Native American artifact the piece as it sits would serve absolutely no purpose.
If found on a Native American site however it may be an artifact in that its scraps from a meal