Green gem

The Green Gem is a rare type of gem in the Crash Bandicoot series. It's known to be an emerald. Along with the other coloured gems this gem is very powerful and opens up secret areas.

Crash Bandicoot
In the original Crash game, where the colored gems were earned on the same way as the clear gems, the Greem Gem is obtained by breaking all the boxes in Toxic Waste. It opens up the Green Gem Paths in Jungle Rollers and Castle Machinery.

Crash Bandicoot 2: Cortex Strikes Back
The Green Gem appears like a bit flat and oblong. In this game it can be obtained in The Eel Deal by completing the secret course behind a fake wall. It opens up the Green Gem Route in Ruination and part of the Multicolour Gem Route in Spaced Out.

Crash Bandicoot 3: Warped
The sprite of the Green Gem is exactly the same as in Crash 2. It can be obtained by completing the Death Route in Flaming Passion. It opens up the Green Gem Route in Gone Tomorrow and part of the Multicolour Gem Route in Bug Lite.

Crash Bandicoot: The Wrath Of Cortex
The Green Gem gets a different sprite. The gem becomes more clear. It can be obtained by completing the Death Route in Wizards and Lizards. It opens up the Green Gem Route in Cortex Vortex.