Icing sugar

Use the same weight and grind to a fine powder in a dry blender. Add 3% cornflour by weight if you need it to stay powdery.

Use the same weight and grind in small batches until fine. It is coarser and may feel gritty in uncooked icings.

Use the same weight and grind to a powder. It is harder to grind and gives a slightly crunchier result.