Whilst the base stamps my look similar there are a number of differences to observe.

zippo lighter dating-69

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.

Around the late 70's the logo was redesigned again, but not implemented into the bottom stamp until 1980.

In July of 1986, lot codes were also being included on all Zippo lighters, showing the month and the year of production.

Up until '45 the bottoms were flat or curved outwards. The quickest hints are barrels, chimney holes, and indented bottoms. Please Click "YES" below if you found this helpful!

There are some exceptions to this (especially slims), but any flat bottoms after about 1955 will have a date code.

The date code enables the collectors to determine the age of the Zippo lighter at a glance.

This is fun and easy to do because every Zippo lighter since 1933 has some kind of identification on the bottom of the Zippo lighter case.

Since 1955, most Zippo lighters have carried a date code stamped on the base.