To convert grammes to kilos divide by 1000. I've generated some hopefully helpful examples randomly below, as with most random sentences please excuse the repetitive and occasionally comic outcomes.

To convert 8.6 grammes into kilos divide by 1000 giving 0.0086 kilos.

How many kilos of emeralds are there in 2.8 grammes? Just divide by 1000 to get the answer of 0.0028 kilos.

In 6.2 grammes of gold there are 0.0062 kilos, to achieve this take 6.2 and just divide by 1000.

You've got 7.2 grammes of platinum but someone only wants to buy that in units of kilos, to change the units divide by 1000. Now you have 0.0072 kilos.

You have 2.8 grammes of diamonds but you need to know how many kilos that is. To get the answer divide by 1000 which gives you 0.0028 kilos.