How to sort different pokemon energy cards by set
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Looking at the "PSA Auction Price Realized" page, I noticed that they have a page dedicated to the Water Energy cards from the base set. My question is how do they tell the difference between a water energy card from the base set and a water energy card from, say, the jungle set? I have a lot of energy cards from the original sets, and I would like to know how they differentiate them, if they do at all. Thanks.
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if numbered to 102 they are base set - the numbers are the key.
Bosox1976