Hello;
This is phosphogypsum, by-product of fertilizer company. chemical composition is given here.
1. Total CaSO4 : 95% wt.
2. Total P2O5 : 1.05% wt.
3. Flourine as F : 0.32% wt.
4. Chloride as Cl : ND
5. Balance : Silica, Iron, Alumina etc.
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