So collectible that they are nearly worthless.
If you have ever been to a thrift store or garage sale that is selling used magazines, you have likely been looking at a whole lot of yellow. Of course I'm talking about shelf after shelf of National Geographic magazine. With a US circulation of over 5 million per issue, multiplied by 12 issues per year, multiplied by over 120 years equals a damn big pile of magazine just about anywhere you might find yourself looking for something to pick. So something this popular must be worth some big bucks, right?
Well, not really.
Sure, if you find some mint issues from the 19th century (before they even had the yellow covers) you can flip them for some real dollars. But, generally speaking, you aren't going to make much in total unless you are selling these suckers in lots of about 50 years worth at a time. Have fun shipping that.
A current issue of Nat Geo has a newsstand price of $6 (although you can get a subscription of 12 issues for $15). After it has been looked at once it is worth about 25 cents on the resale market. This is true for nearly every issue published after World War II. Great magazine, sure, but just too common to really have much value.
But for every antique issue you are lucky to come across, you will see thousands of modern issues, mostly from the 1980s to current era. But don't look away in despair just yet, there may be a nugget of gold in that mountain of yellow.
The issue you are looking to pick is June 1985...
There it is, staring right at you.
It's the famous Afghan Girl with the crazy eyes. That photo is so famous that people are willing to pay about $20 for a copy in good condition. And they really aren't any more uncommon than any other issues from the 1980s. The date is right there on the spine, and I find that while thrift stores aren't in the habit of arranging their magazines chronologically, issues from similar years are usually in close proximity to each other.
A local thrift store near me sells National Geographic published after 1970 for just 10 cents each. Over the past few years I have picked the June 1985 issue and resold it for nearly $20 on six separate occasions! This magazine is consistently selling well and rarely costs more than dollar in the store. Pair it with the April 2002 issue (where the Afghan Girl is "Found" 17 years later) and you may even score a few extra bids.
Remember, that's June 1985. So now you know.