Abstract
The present paper make an attempts to elucidate the water, total nitrogen, organic matter, carbonate, iron, and sulphur contents in the various of phosphate rock, and that of the relation between the ingredient and colour on the phosphate rock. The following conclusions may be drown from the work : The contents of the water, total nitrogen, organic matter, carbonate, iron, and sulphur is regard to the type of deposite and geological age of phosphate rock. Especially, it was shown that the large amounts of iron sulphide as FeS or FeS, is contain in the continental phosphate rock, and that the large amounts the ferrous phosphate as Fe_3(PO_4)_2 aq.is present in the island deposited phosphate rock.The quantities of ferric phosphate as FePO_4 is very small. The greyish yellow, grey or dark grey colur on the phosphate rock is due principally the presence of ferrcus iron compound or organic carbon in the phosphate rock.
