http://www.gemselect.com/actinolite-cats-eye/actinolite-cats-eye.php (see gems here)

http://ikimaru.tumblr.com/tagged/sustuck (inspiration)

NOTE: LISTED IN HEMOSPECTRUM ORDER!!!!!!!!

KARKAT VANTAS
KARKAT VANTAS's gem is Black Opal, lower chest, sickle (fused with Vriska) (bubbled)

aradia megid0
aradia megid0's gem is Fire Opal, right middle knuckle, whip (bubbled)

tAVROS NITRAM
tAVROS NITRAM's gem is Citrine Geode, right back of hand, lance (bubbled)

2ollux captor
2ollux captor's gem is Star Lemon Quartz, left and right wrists, telekinetic abilities, fusion