Circa 800 - 1500 AD.  

This is a life death duality pendant.  Half the body is skeleton.  The other half is living.  The pendant has to what appears to be bone or shell inlayed eyes.

Ownership history is not available.

See photo's for best description.  

Size is approximate 29 mm wide x 39 mm tall x 22 mm deep.  

The weight is 22.8 grams