The U.S. 1851 - 1857 3-cent imperforate stamp has fascinated philatelists for over a century.  The "human" touches that went into engraving the master dies, touching up the plate imperfections, and even mixing the inks are clearly evident in the stamps over 140 years after they were printed.

Dr. Carroll Chase mastered the study of this stamp in 1909, and went on to write an entire book about the imperforate and perforated varieties by 1929.  He continued to refine his study until his death in 1960.  The affordability of the issue to collectors on practically any budget today provides an excellent opportunity to study the stamp that engrossed Dr. Chase for most of his life.

This site offers a brief overview of the characteristics of the stamp that are so wide ranging.  My study focuses on statistics and color, while other specialists focus on plate characteristics and other aspects of the issue.  I include some background information on plates and plating here because the subjects are necessary precursors to statistical and color study.