The part of the excerpt that best develops the theme that different people find value in different things is:
"I cannot conceive," said he, "what pleasure you Europeans find in our yellow clay, but take as much as you like, and great good may it do you."
This line highlights the differing perspectives and values between the King and Candide. The King does not understand the importance that Candide places on the clay, which signifies how individuals may find value in different things based on their backgrounds and experiences.