<prompt> Stag Horn Calculus is made up of:Magnesium ammonium phosphateCalcium oxalateUric AcidCysteine  <response>: Ans. a Magnesium ammonium phosphateRef Bailey and Love 27th Edition, Page 1406Triple Phosphate Stone: Usually Calcium phosphate but sometimes is combined with ammonium and magnesium to form the triple phosphate calculus ammonium magnesium phosphate Also, ka struvite stone Smooth and dirty white and solitary Seen in alkaline urine especially with proteus infection which split urea to ammonia This type of calculus may enlarge to fill all or most of renal collecting system forming a staghorn calculus 