The Japanese system is Air, Thunder, Water, Fire, and Earth. The Chinese system is Metal, Wood, Water, Fire, and Earth. I'm Chinese, so I probably know those things better than you.
I don't see why purple is not one of the more notable colors. To me, the five "primary" colors are red, yellow, green, blue, and purple. But then again, I see yellow as the combination of red and green, purple as the combination of red and blue... Thus I want to have the RGB shards, then combine those shards to make secondary and tertiary colored Crystals and Gems...
OK, we're getting way off topic. I assume that the card itself has no problems now, right?