Historical Zippo references associated with 1968: 5 case/bottom stamp entries, 5 insert entries, and 3 photographed examples. Date codes, materials and insert construction should be assessed together, especially for transitional years.
5 case references5 insert references3 photographed records
Historical context and cautions
Historical dating note
Terry Lyons photographic reference: a Bradford regular-size case shows the 1968 vertical bars pattern (3 left, 3 right), with associated insert front/back and chimney-top photographs. The insert may have been replaced; determine case and insert dates separately.
Typical US regular-production chronology from independent collector research by Hardi Döhler. The ranges overlap, and Canada, Slim, Replica, Sterling, Japan-market and special editions may differ. These are supporting observations, not a definitive date determination.
16-hole chimney — Introduced during 1946; not useful as a precise clue on later inserts. Known period: 1946–9999. Evidence: secondary. Sources: Glen's Zippo Page.16-hole chimney · Historical reference illustration · Source: Glen's Zippo Page
Narrow cam spring — Used to around 1970; narrow springs have been found in 1971 lighters. Known period: 1957–1971. Evidence: supporting. Sources: Glen's Zippo Page.Narrow cam spring · Historical reference illustration · Source: Glen's Zippo Page
Solid flint-wheel rivet — Introduced around 1961; overlaps hollow rivets for several years. Known period: 1961–9999. Evidence: supporting. Sources: Glen's Zippo Page.Solid flint-wheel rivet · Historical reference illustration · Source: Glen's Zippo Page
Interpretation: References may cover multiple years. A documented insert date is not proof of its case production date, and special Replica stamps require separate interpretation.