@Sweettia1 OK SO YOU SEE i noticed that too and then i got confused, maybe the gems actually mean nothing and it's just a coincidence BUT i think that the panel where he wore the blue gem actually chronologically came EARLIER than when he wore the red gem (even though the manhwa presents them in opposite order)
as in when riaz says "its too early for a confession" hes wearing the *blue gem* but then lippie later says to him "do we have that kind of relationship?" she can't remember his face, but she remembers that he wore a *red gem* so maybe by the second time when she was feeling bitter towards him and replied spitefully.. riaz feelings had changed??
BAHAHAAH I THINK I'M JUST READING WAY TOO HARD INTO THIS AND THE AUTHOR WAS JUST LIKE hmmm blue looks pretty today! LOL (but also lippie gave gems to her family as a sign of protection... so surely gems have some sort of meaning in this???)
edit: my brain is going down this rabbit hole and i'd just like to add that in chap 46 (when he first meets her) his gem is also blue and then when he saves her in chap 62 (second time they meet) his gem is now red teehee