The item shown is a Uranium 
jadeite green hobnail glass salt cellar (also known as an open salt dip).
Details
  • Material: It is made of jadeite green milk glass. The glass may also be a type of uranium glass, which causes it to glow under UV light.
  • Pattern: The pattern is a "hobnail" or "diamond points" design, characterized by raised, rounded bumps on the exterior surface.
  • Maker: Similar pieces with this "Gigi" hobnail pattern are produced by Mosser Glass and are inspired by older Fenton Art Glass designs.
  • Function: This item is typically used as a small dish to hold salt or, in modern use, as a votive candle holder.