"Andy" wrote in message
...
Think of it this way, is a 4 carat diamond only double the price of a 2
carat diamond? The bigger it is, the more it costs and the increase in
price is a curve, not linear.

But that's assuming larger sizes are rarer. In the case of lumber,
shouldn't thicker boards require FEWER cuts, and therefore be cheaper
per bf?


No! Diamonds do not have to be cut to be weighed in carats.