Purple gem

The Purple Gem is a rare type of gem in the Crash Bandicoot series. It's known to be an amethyst. 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 Purple Gem is obtained by breaking all the boxes in Lights Out. It opens up the Purple Gem Path in Boulder Dash.

Crash Bandicoot 2: Cortex Strikes Back
The Purple Gem appears like a bit oblong. In this game it can be obtained in Bee-having by reaching a secret area in the stages, which can be accessed by hopping to the top of a stair of Nitro-boxes. It opens up part of the Multicolour Gem Route in Spaced Out. There is no special Purple Gem Route in this game, making it the less important coloured gem to obtain from the five the game contains.

Crash Bandicoot 3: Warped
The sprite of the Purple Gem is exactly the same as in Crash 2. It can be obtained by completing the Death Route in High Time. It opens up the Purple Gem Route in Tomb Time and part of the Multicolour Gem Route in Bug Lite.

Crash Bandicoot: The Wrath Of Cortex
The Purple Gem gets a different sprite. The gem becomes more clear. It can be obtained by completing the Death Route in The Gauntlet. It opens up the Purple Gem Route in Droid Void.