In The Pearl, what does the first pearl buyer tell Kino about the pearl?

The first pearl buyer lies to Kino and tells him the pearl is worthless.... that its only worth is as a curiousity because it is too large. Rather than commend its true value, he devalues it by deeming it unmarketable.

"You have heard of fool's gold," the dealer said. "This pearl is like fool's gold. It is too large. Who would buy it? There is no market for such things. It is a curiosity only. I am sorry. You thought it was a thing of value, and it is only a curiosity."