Power Gem

Power Gems are only seen in Crash Tag Team Racing.

They are purple gem stones that activate the gateways to each of Von Clutch's Motor World's lands. However, to unlock the jump pads in each land, Crash needs to use Power Crystals instead of the gems.

Purple Gems
Power Gems closely resemble purple gems from various other Crash games and like all gem types, unlock a new path (in this case, the entrance to the next land).