What is the value of a 1851 silver coin with a Indian head on one side it does not say in god we trust?

All standard U.S. silver coins issued during that time period used a common design with a picture of Miss Liberty in a seated position. In addition, the motto In God We Trust did not appear on any coin until 1864.

Please post a new question with more specific details including the item's size, denomination, and the design on the other side. It's possible you have a privately-issued coin that could be identified if we had more information.