The game options with the National Geographic Rock and Mineral Card Game Set are endless! Lay all the cards face down and turn over to find a match for a quick memory game. Or play a fun game of trivia by reading aloud the card's short description of the pictured rock or mineral. Can your opponent guess the right answer? Or use the colorfully illustrated deck of 52 playing cards to play any family game! An excellent gift for the rock lover in your family. Includes instructions and 75 gemstones for collecting or keeping score.