How to calculate rate of a gem

Dear everyone.
Suppose a gem costs 1000£ per carat . Will the rate of its 4 carat gem be 441000
how to calculate 5.25 carat Kashmir origin blue sapphire rate from the gem price guide if it is natural unheated .

Hello Raghu! If you have a stone that weights 5.25 cts and the price is 1000 per carat then you just multiply the 5.25 with 1000 which gives you the total price of the gemstone, 5250

Hi, in regard to good quality Sapphire Ruby and other gems, price does depend on size of the gem for instance

do not take these prices literally THIS IS JUST AN EXAMPLE as I do not know what price per carat Kashmir blue is???
Kashmir blue sapphire top quality cut gem

up to 1 ct $1000
next 2 cts $2000 per carat
next 2 Cts could be $3000 to $4000 per carat
top quality gemstone does not stay the same rate from 1 to 5 carats

Thank you Tomi-jC and Syd-prickett.
What I wanted to know is that in some respected institutions in the trade have stated that
rate= caratcaratprice.
how is this to be understood.They are clea that if carat weight is 2carat than price will be 4*price of the stone.
Thanks in advance.

Determining the quality of a gemstone involves what jewelers refer to as the “four C’s.” They are as follows:

4.Carat Weight

Thank you sir, for your reply.