This is a beautiful 1990s Atlantis crystal decanter and matching stopper.  The decanter shape is square, and the brand name is acid-etched on the bottom.

NOTE:  Photographing glass is not my area of expertise.  The pattern is somewhat obscured by reflections; it consists of 2 vertical "rays" on each side with a 4-pointed star about 1/3 up each one.  The four sides are identical.

I haven't been able to identify the name of the pattern, nor do other sellers agree on the name.  I do not have the original box.  #19394 

SIZE:  This decanter measures about 10.5" tall to the top of the stopper.  The base is and 3.5" wide at the base.  The capacity is about 1 1/4 quarts.

BACKGROUND:  This decanter was part of a large collection of glass, china, and silver items I recently purchased from a neighbor who was moving to assisted living.