Easily one of the greatest sets of the 21st Century...lovely design.

For spotting variations in Series 1, look at the Code at the bottom of the back of the card.

Normal Base cards end in 861
Photo Variations end in 901
Sparkle (Hidden Gems) Variations end in 903

For spotting variations in Series 2, look again at the Code at the bottom of the back of the card.

Normal Base cards end in 3764
Photo Variations end in 3808
Sparkle (Hidden Gems) Variations end in 3810

Source: Cardboard Connection website.

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