Geochemistry
The two tables at the end of this section summarize key
multi-element analyses from the Cerro Maricunga deposit, in
particular, elements such as copper, sulphur (indicative of sulphide
mineralization), carbon and mercury. The Cerro Maricunga
mineralization is comparatively clean without any significant
detritus element associations resulting in good gold recoveries with
column leach test averaging 80% gold recoveries on 19 mm (3/4 inch)
crushed mineralization and low to moderate levels of processing
consumables.
Sulphides
Unlike the many gold deposits worldwide, gold at Cerro Maricunga is
not associated with sulphides, such as pyrite (FeS2), but rather is
associated with iron oxides, mainly magnetite (Fe3O4). The Cerro
Maricunga deposit is a sulphide-poor gold system with only rare
sulphides observed even at depths in excess of 500 metres below
surface. Total sulphur (Stotal), the defining element in sulphide
minerals, is low averaging 0.2 to 0.5% with sulphide-related sulphur
(Ssulphide) in the range of 0.01 to 0.1% (see Table 1 & 2 below).
Copper
With sulphides at Cerro Maricunga being rare, the copper content of
the Cerro Maricunga deposit is similarly low, averaging 0.02 to
0.03%. For comparison, the table below summarizes the copper content
of gold dominant deposits in the Maricunga Mineral Belt.
|
Deposit
|
Company
|
% Copper
|
|
Cerro Maricunga Deposit
|
Atacama Pacific
|
0.02 - 0.03
|
|
Volcan Deposit
|
Hochschild
|
0.06
|
|
Maricunga Mine, Pancho Deposit
|
Kinross Gold
|
0.08 - 0.10
|
|
Lobo // Marte Deposits
|
Kinross Gold
|
0.05 // 0.1 - 0.2
|
Copper can be an issue in heap leach operations because many
copper minerals are readily leachable by the cyanide solution that
is applied to the leach pad to extract gold. Cyanide soluble copper
minerals lock up and consume cyanide which adds to the cost of
leaching since additional cyanide must be added to the leach
solutions. Fortunately, the Cerro Maricunga copper has low
solubility with copper recoveries from column leach tests averaging
only 1 to 3%.
|
Table 1 - Geochemical Result from Mineralized and
Non-mineralized Rock, Cerro Maricunga Deposit
|
|
|
|
|
|
|
|
|
|
|
Total
|
Total
|
|
|
Depth
|
Gold
|
Silver
|
Copper
|
Moly.
|
Lead
|
Zinc
|
Mercury
|
Carbon
|
Sulphur
|
|
Zone
|
Sample
|
(m)
|
g/t
|
g/t
|
%
|
ppm
|
ppm
|
ppm
|
ppm
|
%
|
%
|
|
Phoenix
|
CMD009
|
118
|
0.04
|
<0.1
|
0.01
|
0.9
|
1.9
|
89
|
0.01
|
0.05
|
<0.02
|
|
|
CMD009
|
120
|
0.11
|
<0.1
|
0.01
|
1.1
|
1.8
|
99
|
0.02
|
0.08
|
<0.02
|
|
|
CMD009
|
306
|
0.00
|
<0.1
|
0.00
|
0.5
|
2.2
|
54
|
0.01
|
0.08
|
<0.02
|
|
|
CMD009
|
314
|
0.01
|
<0.1
|
0.00
|
0.5
|
3.0
|
88
|
<0.01
|
0.14
|
<0.02
|
|
Crux
|
CMD014
|
170
|
0.55
|
0.2
|
0.03
|
2.0
|
5.4
|
160
|
<0.01
|
0.13
|
0.67
|
|
CMD014
|
172
|
0.30
|
0.2
|
0.03
|
2.2
|
3.8
|
201
|
<0.01
|
0.18
|
0.91
|
|
CMD014
|
350
|
0.65
|
0.3
|
0.02
|
1.7
|
3.0
|
161
|
<0.01
|
0.19
|
0.94
|
|
CMD014
|
352
|
0.05
|
0.2
|
0.01
|
2.3
|
4.6
|
155
|
<0.01
|
0.17
|
0.63
|
|
CMD014
|
356
|
0.14
|
0.3
|
0.01
|
2.5
|
6.0
|
193
|
<0.01
|
0.16
|
1.13
|
|
CMD014
|
370
|
0.27
|
0.2
|
0.02
|
3.7
|
5.4
|
467
|
<0.01
|
0.14
|
0.99
|
|
CMD014
|
374
|
0.40
|
0.1
|
0.02
|
3.0
|
2.0
|
238
|
<0.01
|
0.17
|
0.42
|
|
CMD014
|
380
|
0.58
|
0.1
|
0.02
|
3.0
|
2.4
|
102
|
<0.01
|
0.11
|
0.38
|
|
CMD014
|
388
|
0.71
|
0.2
|
0.02
|
2.8
|
1.5
|
155
|
<0.01
|
0.16
|
0.54
|
|
CMD014
|
390
|
0.38
|
0.2
|
0.02
|
1.2
|
2.1
|
197
|
<0.01
|
0.15
|
0.19
|
|
CMD014
|
394
|
0.37
|
0.2
|
0.01
|
1.1
|
2.5
|
172
|
<0.01
|
0.17
|
0.32
|
|
|
CMD014
|
396
|
0.18
|
0.2
|
0.01
|
1.5
|
2.5
|
195
|
<0.01
|
0.14
|
0.62
|
|
Crux
|
CMD016
|
206
|
0.08
|
<0.1
|
0.01
|
1.9
|
2.6
|
79
|
<0.01
|
0.09
|
0.86
|
|
|
CMD016
|
216
|
0.08
|
<0.1
|
0.01
|
3.0
|
2.5
|
58
|
0.02
|
0.07
|
0.70
|
|
|
CMD016
|
220
|
0.06
|
0.1
|
0.01
|
1.0
|
2.5
|
65
|
0.01
|
0.08
|
0.58
|
|
|
CMD016
|
224
|
0.23
|
<0.1
|
0.01
|
0.8
|
1.9
|
69
|
<0.01
|
0.10
|
0.45
|
|
Phoenix
|
CMD019
|
68
|
0.13
|
<0.1
|
0.01
|
0.3
|
2.2
|
83
|
0.01
|
0.11
|
<0.02
|
|
CMD019
|
116
|
0.03
|
<0.1
|
0.00
|
0.5
|
2.4
|
37
|
<0.01
|
0.04
|
<0.02
|
|
CMD019
|
118
|
0.05
|
<0.1
|
0.00
|
0.6
|
2.5
|
48
|
<0.01
|
0.09
|
<0.02
|
|
CMD019
|
192
|
0.12
|
<0.1
|
0.01
|
1.0
|
3.7
|
62
|
0.02
|
0.07
|
<0.02
|
|
CMD019
|
222
|
0.09
|
<0.1
|
0.01
|
0.8
|
2.5
|
56
|
<0.01
|
0.07
|
<0.02
|
|
CMD019
|
226
|
0.08
|
<0.1
|
0.01
|
1.4
|
2.5
|
65
|
<0.01
|
0.06
|
<0.02
|
|
|
CMD019
|
236
|
0.09
|
<0.1
|
0.01
|
0.5
|
2.0
|
68
|
0.01
|
0.12
|
<0.02
|
|
Phoenix
|
CMD026
|
60
|
0.04
|
<0.1
|
0.00
|
1.8
|
4.1
|
74
|
<0.01
|
0.04
|
<0.02
|
|
|
CMD026
|
72
|
0.02
|
<0.1
|
0.00
|
3.2
|
2.5
|
38
|
<0.01
|
0.06
|
<0.02
|
|
|
CMD026
|
146
|
0.17
|
<0.1
|
0.01
|
1.6
|
3.9
|
347
|
<0.01
|
0.18
|
0.26
|
|
|
CMD026
|
156
|
0.13
|
<0.1
|
0.02
|
4.2
|
2.6
|
51
|
<0.01
|
0.15
|
0.13
|
|
|
CMD026
|
160
|
0.04
|
<0.1
|
0.01
|
4.4
|
1.8
|
41
|
<0.01
|
0.10
|
0.03
|
|
|
CMD026
|
162
|
0.05
|
<0.1
|
0.01
|
4.3
|
1.8
|
52
|
<0.01
|
0.10
|
0.02
|
|
|
CMD026
|
180
|
0.01
|
<0.1
|
0.01
|
0.6
|
2.0
|
41
|
<0.01
|
0.05
|
0.05
|
|
|
CMD026
|
202
|
0.02
|
0.2
|
0.03
|
3.5
|
2.1
|
38
|
<0.01
|
0.06
|
0.09
|
|
|
CMD026
|
212
|
0.16
|
0.2
|
0.02
|
1.1
|
2.6
|
56
|
<0.01
|
0.09
|
0.14
|
|
|
CMD026
|
230
|
0.10
|
<0.1
|
0.02
|
1.3
|
2.0
|
93
|
<0.01
|
0.08
|
0.03
|
|
|
CMD026
|
238
|
0.86
|
0.1
|
0.04
|
3.0
|
2.2
|
159
|
<0.01
|
0.13
|
0.26
|
|
|
CMD026
|
254
|
0.84
|
0.1
|
0.05
|
3.5
|
2.4
|
63
|
<0.01
|
0.11
|
0.22
|
|
|
CMD026
|
264
|
1.02
|
0.1
|
0.03
|
1.0
|
2.3
|
91
|
<0.01
|
0.11
|
0.31
|
|
|
CMD026
|
288
|
2.33
|
0.3
|
0.06
|
2.2
|
2.0
|
97
|
<0.01
|
0.12
|
0.13
|
|
|
CMD026
|
294
|
1.38
|
0.1
|
0.04
|
1.0
|
2.5
|
79
|
<0.01
|
0.18
|
0.60
|
|
|
CMD026
|
300
|
1.47
|
0.2
|
0.03
|
2.9
|
2.4
|
76
|
0.01
|
0.06
|
0.28
|
|
|
CMD026
|
314
|
1.06
|
0.1
|
0.03
|
2.9
|
2.8
|
110
|
<0.01
|
0.14
|
0.46
|
|
|
CMD026
|
326
|
1.44
|
0.1
|
0.04
|
2.6
|
2.1
|
77
|
<0.01
|
0.12
|
<0.02
|
|
|
CMD026
|
330
|
0.77
|
<0.1
|
0.03
|
2.5
|
2.4
|
91
|
<0.01
|
0.11
|
0.16
|
|
|
CMD026
|
336
|
0.11
|
<0.1
|
0.01
|
0.8
|
2.1
|
88
|
<0.01
|
0.13
|
0.14
|
|
|
CMD026
|
352
|
0.72
|
0.2
|
0.03
|
2.5
|
1.6
|
56
|
<0.01
|
0.06
|
0.04
|
|
|
CMD026
|
364
|
1.71
|
0.2
|
0.05
|
2.6
|
2.1
|
101
|
<0.01
|
0.10
|
0.12
|
|
|
CMD026
|
376
|
1.19
|
0.2
|
0.04
|
0.8
|
1.5
|
85
|
<0.01
|
0.13
|
0.04
|
|
|
CMD026
|
392
|
0.70
|
0.5
|
0.04
|
1.7
|
1.7
|
84
|
<0.01
|
0.13
|
0.06
|
|
|
CMD026
|
406
|
0.00
|
<0.1
|
0.00
|
0.9
|
1.5
|
64
|
<0.01
|
0.08
|
0.04
|
|
|
CMD026
|
412
|
1.67
|
0.2
|
0.05
|
0.7
|
3.1
|
89
|
<0.01
|
0.09
|
0.07
|
|
|
CMD026
|
414
|
1.35
|
0.2
|
0.05
|
0.9
|
2.5
|
96
|
<0.01
|
0.10
|
0.06
|
|
|
CMD026
|
418
|
1.38
|
0.2
|
0.04
|
2.6
|
1.5
|
85
|
<0.01
|
0.09
|
0.04
|
|
|
CMD026
|
442
|
2.18
|
0.3
|
0.06
|
2.7
|
1.5
|
82
|
<0.01
|
0.07
|
0.09
|
|
|
CMD026
|
462
|
0.36
|
<0.1
|
0.02
|
2.2
|
1.8
|
144
|
<0.01
|
0.18
|
0.19
|
|
|
CMD026
|
470
|
0.03
|
<0.1
|
0.01
|
0.7
|
1.6
|
98
|
<0.01
|
0.09
|
0.03
|
|
|
CMD026
|
482
|
0.04
|
<0.1
|
0.02
|
0.8
|
1.8
|
78
|
<0.01
|
0.09
|
0.15
|
|
|
CMD026
|
492
|
0.10
|
<0.1
|
0.02
|
1.0
|
1.9
|
76
|
<0.01
|
0.12
|
0.09
|
|
|
CMD026
|
500
|
0.06
|
<0.1
|
0.02
|
2.5
|
1.4
|
79
|
<0.01
|
0.13
|
0.13
|
|
|
CMD026
|
516
|
0.03
|
<0.1
|
0.01
|
5.1
|
1.6
|
79
|
<0.01
|
0.08
|
0.10
|
|
|
CMD026
|
526
|
0.07
|
0.1
|
0.02
|
0.9
|
2.3
|
165
|
<0.01
|
0.20
|
0.14
|
|
|
CMD026
|
532
|
0.05
|
0.2
|
0.01
|
3.5
|
5.9
|
208
|
<0.01
|
0.11
|
0.02
|
|
Crux
|
CMD027
|
222
|
0.10
|
<0.1
|
0.00
|
2.5
|
1.9
|
188
|
<0.01
|
0.17
|
0.40
|
|
|
CMD027
|
228
|
0.05
|
<0.1
|
0.00
|
2.0
|
2.0
|
136
|
<0.01
|
0.13
|
0.31
|
|
Phoenix
|
CMD037
|
42
|
0.02
|
<0.1
|
0.01
|
0.7
|
1.5
|
56
|
<0.01
|
0.04
|
0.08
|
|
|
CMD037
|
126
|
0.01
|
<0.1
|
0.01
|
2.2
|
3.4
|
77
|
<0.01
|
0.08
|
0.02
|
|
|
CMD037
|
136
|
0.01
|
<0.1
|
0.01
|
1.9
|
1.3
|
60
|
<0.01
|
0.10
|
0.02
|
|
|
CMD037
|
166
|
0.02
|
0.1
|
0.01
|
1.6
|
1.1
|
52
|
<0.01
|
0.07
|
0.09
|
|
Table 2 - Cerro Maricunga Geochemistry
|
|
Zone
|
Met.
Comp.*
|
Drill Hole
|
Depth
|
Au
|
Cu
|
Fe
|
S
(Total)
|
S
(Sulphide)
|
C
(Total)
|
C
(Organic)
|
|
metres
|
ppm
|
%
|
%
|
%
|
%
|
%
|
%
|
|
Phoenix
|
Comp. 1
|
CMD-026
|
260-272 / 280-292
|
1.45
|
0.05
|
2.36
|
0.27
|
0.04
|
0.15
|
0.04
|
|
Comp. 2
|
CMD-037
|
76-94
|
0.81
|
0.08
|
2.60
|
0.16
|
0.01
|
0.11
|
0.02
|
|
Comp. 3
|
CMD-010
|
30-40 / 50-56
|
0.40
|
0.02
|
2.64
|
0.40
|
0.06
|
0.19
|
0.02
|
|
Lynx
|
Comp.4
|
CMD-049
|
194-216
|
1.93
|
0.07
|
2.63
|
0.11
|
0.06
|
0.13
|
0.03
|
|
Comp. 5
|
CMD-058
|
146-154
|
0.80
|
0.02
|
3.06
|
0.11
|
0.03
|
0.09
|
0.03
|
|
CMD-049
|
74-86
|
|
Comp. 6
|
CMD-058
|
108-118
|
0.37
|
0.01
|
2.66
|
0.11
|
0.02
|
0.14
|
0.05
|
|
CMD-038
|
64-72
|
|
Crux
|
Comp. 7
|
CMD-011
|
38-44
|
0.13
|
0.03
|
2.50
|
0.35
|
0.04
|
0.09
|
0.04
|
|
CMD-056
|
46-54
|
|
Comp. 8
|
CMD-014
|
230-248
|
0.73
|
0.03
|
2.69
|
0.78
|
0.11
|
0.16
|
0.05
|
|
Comp. 9
|
CMD-027
|
48-56
|
0.37
|
0.03
|
2.78
|
0.27
|
0.06
|
0.11
|
0.04
|
|
CMD-031
|
58-68
|
|
·
See table “Composite
Samples by Zone and Depth (Plenge Laboratorio)”
in the Metallurgical section
|
|
|
