Classification

Metallurgical silicon is classified according to its purity and the different percentage of the main impurities.
The following qualities are typical on the market:

Silicon 553: iron max. 0,5 %, aluminum max. 0,5 %, calcium max. 0,3 % (standard quality)

Silicon 441: iron max. 0,4 %, aluminum max. 0,4 %, calcium max. 0,1 % (refined quality)

Silicon 3303: iron max. 0,3 %, aluminum max. 0,3 %, calcium max. 0,03 % (special quality)

Silicon 2202: iron max. 0,2 %, aluminum max. 0,2 %, calcium max. 0,02 % (low iron quality)