"You have received a Time Gem! Collect them to extend your game after the timer bar empties!"
— In-game description from Bejeweled 3
Time Gem is a type of gem that only appears in Lightning mode (known as Speed mode in the HTML version of Bejeweled) of Bejeweled 3 and the iOS and HTML versions of Bejeweled. It has two gem types: +5 and +10. These gems add five or ten seconds to the Time Extension tank or additional points when the tank completed filled. When there is only five seconds left in the round, the text on the gems will start flickering. At the end of the round, the +5 gem becomes a Flame Gem and a +10 gem becomes a Star Gem. If Time Up appears, then the gems will award five or ten times the base value depending on type during the Last Hurrah.