I consider these 'sketches' in metal.  A little bit imperfect, strips of lightweight aluminum wire are hammered and pinned with tiny sterling rivets.  They have a lovely brushed finish to them and are large enough to be noticed, but light enough that they will not weigh you down.  They hang on sterling silver earwires.  
With earwire, they measure 2.25" tall and are 1.75" across.