13c Liberty Bell Stamp (1975): How to Identify It

• Design and inscription: the Liberty Bell design commemorates the bell's 1751 origin, marking the fiftieth anniversary of William Penn's 1701 'Charter of Privileges,' which granted religious and personal liberty to the Pennsylvania colonists.
• Series debut: issued October 31, 1975, on the eve of America's bicentennial year, in booklet form depicting the Liberty Bell, marking the start of a new definitive series called the 'Americana Issue.'

The same design was issued in more than one form. Which one you have changes the catalog listing:

• Booklet panes (Scott 1595a/1595b/1595c/1595d): Sold bound as booklet panes of 6, 7-with-label, or 8 stamps rather than as a full perforated sheet.
• Coil (Scott 1618, 1975): A coil-format version of the same design, sold in rolls rather than sheets or booklets.

This Liberty Bell stamp belongs to the Americana series that succeeded the Prominent Americans series; the Prominent Americans series' own 13-cent value pictures John F. Kennedy, not the Liberty Bell. See the 13c John F. Kennedy page.

• Measure the perforations with a gauge; the same design often exists in two or three gauges, and that is usually what separates the common one from the scarce one.
• Sheet, coil or booklet: coils have two straight edges on opposite sides; booklet panes have one or two straight edges from the pane edge.
• Tagging: hold it under a longwave UV lamp; tagged and untagged printings of the same design are listed separately.
• Condition (centering, gum, cancel) is a separate question from identification.

Lay the stamp flat on a dark background in daylight, fill the frame, and keep the phone parallel so the perforations are not distorted. Photograph the back too if there is a watermark or gum question. The app reads the design and denomination; the perforation and tagging checks above settle which listing it is.