I recently downloaded Bejeweled-Blitz to my iPhone. A recent update has changed the application so that between each game, I am asked if I want to purchase a "Rare Gem". There are 5 different types of Rare Gems and, from what I can gather, the only way to purchase them is to purchase the one you are offered, in between each round.
I think these rare gems are offered at random, however, some of them seem be more rare than others. Also, each gems has an explanation as to what it does. I'm not interested in that. What I would like to know is when or if I purchase one of these gems, how do I use it?
Will they automatically appear in my next game? Will they only appear for a limited number of rounds? Is it a one-time purchase, and then these gems will randomly show up on the board?
I'm curious because even though I enjoy the game, I'm not interested in spending any money to buy additional coins. Since the coins I do have are precious, I don't want to buy and of these gems if they are to expensive for the reward. The benefit of the purchase may be subjective to the user, however, knowing the exact mechanics of how these gems are used can help me figure out whether I'd like to buy them or not.