|Introduced||June 9, 2015|
|Rare Gem type||Limited|
When the player begins a game with Aquamarine activated, a random number of unique blue gems that resemble trident spearheads drops alongside the other gems into the board. A spearhead functions identically to a Flame Gem, except a spearhead clears 10 gems in a 5×3 oval-shaped pattern instead. A spearhead, when cleared from the board, also changes all the red and orange gems within its row and the adjacent rows to blue; Flame Gems transformed by this effect become spearheads. The base value for clearing a spearhead is 500 points. While Aquamarine is active, spearheads replace random blue gems throughout the game, and Flame Gems created using blue gems become spearheads instead.
After the Last Hurrah, a Coin bonus occurs in which nine spearhead icons appear in a 3×3 arrangement. When the player selects an icon, it reveals a numerical Coin value that is then added to the player's Coin total. The Coin payouts the bonus offers are 1,000, 2,000, 4,000, 6,000, 9,000, 15,000, 50,000, 100,000, and 250,000.
- The name of this Rare Gem is a double entendre; it not only refers to the color of the same name but also a light-blue or greenish-blue variety of beryl.
- The mermaid king-like sprite that appears after the Last Hurrah resembles Poseidon the Greek god of the sea (or Neptune, the Roman counterpart).
- The trident is the weapon of Poseidon and Neptune, and it is also the astronomical symbol that represents the planet Neptune.
- Aquamarine's harvest screen shows the Rare Gem changing white gems to blue, but this does not happen in-game.