River Rock Jewelry
River Rock comes from the Otherworld and isn't found naturally in the Human World. Even in Faery, it is rare and therefore quite valuable. Found near water, it often forms near the thresholds between our two worlds.
I'm not aware of any medicinal uses for River Rock. However, the gemstone stops sound from traveling on the wind, helping the person wearing it hide from the fae. This ability stops working if a Sidhe is nearby.
-Tressa/The King’s Jewel Series