normal oem xenons are 4000k and pretty yellow looking the projector part of the headlight gives the oem xenon its bluey/purple tint and its spread.
h.i.d's are xenons but usually are 6000k so that a blueish oem looking tint is acheived without the glass orb projector part.
the higher the amount of K the more into purple you get evetually into ultra violet
eg
4000k yellowy white
6000k ice whitey blue
8000k bluey purple
10000k purple
12000k purple/violet and unusable on the road imo.