What was one thing Merlock, a trader, said about Aragon's stone?

From the text:

Merlock grimaced. "Unfortunately, neither do I. But I can tell you this much: the white veins are the same material as the blue that surrounds them, only a different color. What that material might be, though, I haven't a clue. It's harder than any rock I have seen, harder even than diamond. Whoever shaped it used tools I have never seen — or magic. Also, it's hollow." pg. 24

Merlock tilted the stone toward them. "You will find no scratches or blemishes where the dagger struck. I doubt I could do anything to harm this stone, even if I took a hammer to it." pg. 25