Instructions
Look for the traditional rectangular shape of the Zippo lighter, remembering that some variations on this original design were created. Open your Zippo lighter and inspect the removable internal lighter system, making sure that it is in place. If it is not functional, avoid concern because the company offers free repairs to every lighter they have ever released.
Turn your Zippo lighter upside down and look for the authentic Zippo stamp on the bottom. Make sure your lighter has the word "ZIPPO," printed all in caps, stamped into the bottom your lighter. Remember, the Zippo company used different lettering throughout the years, but all are clearly stamped with the company name. Look for the "PAT" stamp, with patent numbers, to identify Zippo lighters manufactured between 1933 and 1956. The Zippo lighters between these years are collector's items. Look for a series of dots, --from one to four -- for lighters manufactured between 1957 and 1965.
Identify the date of Zippo lighters manufactured between 1966 and 1973 by a series of straight lines on the stamp. Look for the slanted lines on the stamp to identify lighters made between 1974 and 1986. Inspect the bottom for a letter and a roman numeral for lighters made between 1986 and 2000, after which they removed the roman numerals and the company began using numbers to represent the manufacturing year.
Look for the certificate of authenticity and orange sticker across the back of your lighter, but you may not find either if your lighter has been heavily used in the past. Check the box that your lighter came in. Remember that Zippo used numerous different cases, from small plastic black boxes to larger, ornamental collector's boxes. Save the box for your Zippo, as collector boxes can add value to your Zippo.
Inspect your Zippo carefully, both inside and out. Make sure that the case opens smoothly and that your Zippo face is not scratched or damaged. Check the internal mechanism and make sure that the lighter wheel spins smoothly and that your flint channel is not bent or damaged.