Blue gem

The Blue Gem is one of the coloured Gems, that first featured in Crash Bandicoot. It is most likely a sapphire. It is also featured in Crash Bandicoot 2: Cortex Strikes Back, Crash Bandicoot 3: Warped, Crash Team Racing, Crash Bandicoot: The Wrath of Cortex and Crash Nitro Kart, usually required to open a new level or area.

Crash Bandicoot
In the original Crash game, the Blue Gem was found on the level Toxic Waste, on the third island. It was obtained simply by finishing the level without dying and collecting every box. It opened three Gem Paths allowing for that levels Gem to be obtained - Rolling Stones, Cortex Power and Jaws of Darkness.

Crash Bandicoot 2: Cortex Strikes Back
The Blue Gem returns in the second game, when the Coloured Gems took different shapes. The Blue Gem is now flatter and wider than it was in the first game. In this game it can be obtained on the very first level, Turtle Woods. Rather than breaking every box, it is acquired by not breaking a single box, including Checkpoint boxes. It opens up the Blue Gem Route in Hang Eight and part of the Multicolour Gem Route in Spaced Out.

Crash Bandicoot 3: Warped
The Blue Gem is back for the third installment, retaining the new look it got from the previous installment. It can be obtained by completing the Death Route in Tomb Wader from the fourth warp room. It opens up the Blue Gem Route in Sphynxinator and part of the Multicolour Gem Route in Bug Lite.

Crash Team Racing
The Blue Gem also appears in this racing spin-off installment. If the player completes the CTR Challenges on the race tracks Sewer Speedway, Tiger Temple, Dragon Mines and N. Gin Labs, to collect all blue CTR Tokens, then the Blue Gem Cup will be available to play, where the four races can be raced again. If the player wins the most points from all four races, they win the Blue Gem. It is required to complete the game because the other four Gems are needed to unlock the race Turbo Track. The Blue Gem also unlocks Komodo Joe for the player to play as.

Crash Bandicoot: The Wrath Of Cortex
The Blue Gem returns for this installment and it gets a different sprite. The gem becomes more clear than normal. It can be obtained by completing the Death Route in Arctic Antics. It opens up the Blue Gem Route in Tsunami.

Crash Bandicoot: The Huge Adventure
The blue gem returns in Crash Bandicoot The Huge Adventure for GBA with a sprite similar to the Clear Gem. It is possible to get it in Ruined. The move Death Tornado Spin is required to obtain it.

Crash Bandicoot 2: N-Tranced
The blue gem returns in this game, however for a different purpose then gem paths. In this game, there are blue gem shards, found on the levels Tiki Torture, Magma Mania, Mister Lava Lava, and Eruption Disruption. The blue gem shards are used to unlock the level Fire Walker. In Fire Walker there is no crystal as it is replaced by a blue gem.