228 FANNING AND EDDINGFIELD. 
of gold in the tails and slimes, and (4) the probable action of a 
Wilfley table. 
The results of the tests are given in Table XI. 
TABLE XI.—_First panning test. Lot No. 1. 
eee Value Composition of product. 
Product Weight value per aoe | | 
END tonof | ston of | Goldin | pyrite Iron_ | Metallic 
product. Sahai original. yrite. | minerals. minerals. 
| 
Grams. | Per cent.| Pesos. Pesos. | Per cent.| Per cent.| Per cent.| Per cent. 
Original heads__| 100 = |_--------- 210.30 210280) he Sa eens | Se eee Joaoeccoet eee ee 
| 
Gold recovered _|_---------]----------|---------- 63. 40 80:00) |2===..--=2}: 5222-22] See eee 
Middlings: 
Nonmag- 
netic______ 34.40 34. 40 128.40 42.90 20.28 50 10 
Magnetic ___ 52.41 52. 41 2.40 1.30 0.59 3 by A nee 
Tailings ________ 10. 76 10.76 16. 80 1.80 0. 86 20 10 70 
Slimes====22sse5 2.43, 23438522. eaes 101. 90 48. 2) |2-5-----= 4] 3 Se ee 
—— 
In the test tabulated above, the sample was panned by hand, 
giving (1) free gold, (2) middlings, (3) tailings, and (4) slimes. 
The gold was cupelled and weighed; the middlings were treated 
by magnet to give magnetic and nonmagnetic products; the tail- 
ings were assayed directly; but insufficient slimes were obtained 
to make a satisfactory assay, although the gold content was very 
high. This test was merely preliminary, but it showed the pres- 
ence of high values in free gold. 
Where 1 ton of black sand was concentrated by panning, 63.40 
pesos of gold were obtained giving an extraction of 30 per cent. 
This left a middlings product worth 51.20 pesos per ton, and a 
tailings product worth 16.80 pesos per ton. If the middlings 
were treated magnetically, we could obtain a nonmagnetic prod- 
uct worth 128.40 pesos per ton and a magnetic product worth 
2.40 pesos per ton. The great advantage of magnetic treat- 
ment was at once indicated by this test and led to a magnetic 
test as shown on page 230 where the original was magnetically 
treated and gave a nonmagnetic product containing 97.21 per 
cent of the gold. 
The results of the panning test given in Table XI were con- 
firmed by a second test in which the sample was crushed through 
40-mesh and extreme care taken in the panning. In this test 
only gold and tailings were separated. The tailings were then 
given magnetic treatment. The results are tabulated as follows: 
