A very small volume (< 0.1 mL) of the stock haematite solution is used to directly prepare the solution for the spectrophotometer. 

1 mL of the final solution after adding the KSCN is diluted with water in the spectrophotometer cell. 

The stock haematite is diluted in a 250 mL volumetric flask, and 10 mL of this solution is used to prepare the 100 mL of solution for the spectrophotometer.