On average, black and blue are 82 yuan/carat. Deep blue sapphire 540 yuan/carat, exotic deep blue sapphire 600 yuan/carat, starlight sapphire 9 17 yuan/carat, brilliant (exotic) topaz 980 yuan/carat, brilliant empty shell sapphire 1500 yuan/carat. But there is a big difference.

(There is no good answer, ask yourself and answer yourself)