[Molly's scarlet eyes go wide and there's an almost childlike mirth in them that you wouldn't expect to see on someone with eyes quite like that. He is absolutely delighted.] I can honestly say I have never heard of anything like that, but that is amazing, and if the non-living variety of rocks are your brethren in any way, I will give the utmost respect to any baubles I come across.

[That last part is a bit facetious, but he's so utterly endeared that he's talking to a SENTIENT DIAMOND that it's hard to take as offensive or insincere.]