The date coding procedure was first started in the mid 50's when the date codes were stamped on the bottom of the Zippo lighter's case.
Although the original purpose for date coding was for quality control, the procedure became an invaluable tool for the Zippo lighter collector.
I have seen some earlier stamping 1954 zippo cases, with this later insert, showing that zippo was using up all the older cases during late 1954.
While the information for dating a Zippo is widely available, it isn't that handy to find it all in a single location.
The Zippo lighters made in 1933 and up till the mid 1950's have "Zippo" stamped in block letters on the lighter case.
A new Zippo logo was developed in the 1940's but was not implemented until 1955.
The Zippo script logo was developed in the late 40s and was phased-in on the lighter bottom stamp around 1955. About 13.5 million lighters were produced by Zippo Canada.
These lighters are now sought after collector's items and popular souvenirs for visitors to Vietnam.Zippo Canada opened in August 1949 and was the only place, other than Bradford, where Zippo lighters were produced.Operations included the final set-up of the lighter case and insert, surface engraving, cleaning, repair clinic, Items such as packaging and instruction pamphlets, were all “Made in Canada” Dates and timelines about these changes, are VERY difficult to nail down to an exact date, but these are fairly close, based on written info by Zippo, as well as other collectors that have taken the time to share their knowledge with me.The new logo was a script version of the word "Zippo" and was phased in about that time along with the year coding by the use of dots (.).Over the years, the dating codes has been modified, several times over like for instance in 1966 till 1973 the code was denoted by a combination of vertical lines (|), 1974 until 1982 with forward slashes (/), and 1982 until the middle of 1986 with backslashes (\).This should provide the information to fix a relatively precise date for any Zippo lighter.