BLACK SANDS OF PARACALE. PAL 
TABLE XXII.—Screen, amalgamation test. Lot No. 1. 
(Showing distribution in a ton of the orig: 
inal sand.) 
. Gold . 
a Seren. reads.» | 8malea-| tatings.| very. 
Mesh. Pesos. Pesos. Pesos. | Per cent. 
31.00 22. 96 8.04 17. 82 
47.16 39, 22 7.94 30. 40 
18.10 12.16 5. 94 9.47 
10. 12 7.74 2.38 6. 05 
9.82 4.34 5. 48 3.38 
3.98 3.04 0. 94 2.37 
3. 60 1.20 2.40 0. 98 
4.42 3. 68 0. 74 2. 87 
128.30 94. 34 33. 96 73. 29 
8 The loss in this operation largely was due to sliming and repeated grinding. The original 
assay of the heads gave a value of 211 pesos. 
The effect of grinding the original ore through various meshes, 
followed by amalgamation, is shown in Table XXIII. 
TABLE XXIII.—Amalgamation tests. Lot No. 1. 
Assay of | Assay of Gold fs 
Product. No. jheads per] tails per| saved Gold Discrep- 
ton. ton. per ton. | S#Vee- OEY 
Pesos. Pesos. Pesos. | Per cent. Pesos. 
QOriginalesle oo tes teks Stee e 1 211.20 76. 80 84. 00 39.7 | (—)50.40 
2 235. 20 91.80 115. 70 49.4 | (—)27.70 
ey 3 202. 80 67. 40 110. 00 54.5 | (—)25.40 
(0) 1 put th h 60-mesh____---_ 
Ee Te 4| 216.00| 93.00] 124.70 57.6| (+) 1.70 
5 211.20 67. 40 156. 00 73.8 | (+)12.20 
Original through 80-mesh ____________ 6 235. 20 49. 60 177. 40 76.6 | (—) 8.20 
Original, tube-milled for 6 hours -_--- 7 169. 80 15. 20 154. 60 91.0 none 
The original ore gave an extraction of 
39.7 per cent actual 
gold recovered, the 60-mesh gave an average of 58.8 per cent, 
the 80-mesh gave an extraction of 76.6 per cent, and the tube- 
milled product gave an extraction of 91 pe 
show a steady increase of extraction with 
r cent. These results 
greater pulverization 
as would naturally be expected. Variations occur in the ex- 
tractions of the 60-mesh ore, and it is 
either a variation in the amount of free 
splits, or else there is an actual loss of gold in some of the tests. » 
evident that there is 
gold in the different 
