418 On the Chemical Composition of Phosphatic Minerals 
Detailed Composition of Two Samples of Eicn Bordeaux 
Phosphate. 
Moisture 
"Water of combination 
* Phosphoric acid 
Lime 
Magnesia 
Fluorine (by diifcrence) . . 
fCarbonic acid 
Sulphuric acid 
Oxide of iron 
Alumina 
Insoluble siliceous matter 
* Equal to tribasic phosphate of lime . 
t Equal to carbonate of lime . . . . 
No. 1. 
No. 2. 
2-28 
2-52 
35-51 
47-81 
•12 \ 
■89 / 
3-28 
1-24 
33-72- 
44-23 
1-74 
5-06 
■64 
2-80 
2-37 
3-26 
2- 66 
6-42 
3- 45 
100-00 
100-00 
77-52 
11-50 
73-61 
7-40 
General Composition of High Quality French Phosphates. 
No 
. 1. 
No 
. 2. 
No 
3. 
No 
.4. 
No 
5. 
No 
. 6. 
No. 
2 
60 
2 
90 
3 
01 
3 
07 
Water of combination 
2 
62 
1 
01 
2 
11 
50 
43 
3 
50 
4- 
34 
46 
34 
91 
34 
01 
35 
30 
34 
91 
34 
71 
33- 
46 
11 
48 
16 
46 
77 
46 
14 
47 
79 
46 
73 
48- 
Oxide of iron and alumina,! 
carbonic acid, &c / 
10 
77 
9 
44 
11 
61 
12 
40 
12 
07 
11 
01 
10- 
Insoluble siliceous matter . . 
3 
44 
3 
58 
2 
49 
2 
59 
1 
80 
4 
05 
3- 
100 
00 
100 
00 
100 
00 
100 
00 
100 
00 
100 
00 
100- 
* Equal to tribasic phos-! 
phate of lime .. . . j 
75 
•23 
76 
21 
74 
24 
77 
06 
76 
21 
75 
77 
73- 
Composition of French Phosphate of Medium Quality. 
No 
1. 
No 
2. 
No. 3. 
No. 4. 
No 
5. 
No. 6. 
Water of combination 
2 
89 
58 
)' 
22 
/ 1-64 
\ 1-64 
6-02 
3-34 
76 
6-70 
31 
50 
31 
68 
30-47 
30-74 
30 
07 
29-02 
41 
12 
36 
20 
44-69 
41-65 
31 
58 
37-12 
Oxide of iron and alumina,'! 
carbonic acid, <&c / 
13 
73 
19 
19 
17-43 
13-71 
22 
15 
.15-08 
Insoluble siliceous matter.. 
10 
18 
5 
71 
4-13 
4-54 
6 
44 
12-08 

100 
00 
100 
00 
100-00 
100-00 
100 
00 
100-00 
♦ Containing tribasic phoB-) 
phate of lime . . . . ) 
68 
76 
69 
16 
66-52 
67-10 
65 
64 
63-35 
