4 blue cut glass hearts joined to make a shamrock. simple.

This brooch has four heart shaped cut glass stones encasing a rhinestone. It forms a shamrock shape.  It is set in a vermeil base. The word "vermeil" is a French word which came into use in the English language, mostly in America, in the 19th century silver gilt. vemeil  is a mix of metals.  This is most probably from the 1940's.  It is not marked which makes it harder to identify.  What I admire the most is the clarity of the blue glass.  It is a petite little pin that has a 1" diameter.