43-101 2008 Technical Report On The La Fortuna Project, Durango ...

The amount of gold reported recovered from heaps 1 and 2 were 325.50 ounces and 320.62 ounces of gold
respectively. This gold was sold on the market in 2006 (Babcock, 2006, Northern Front, 2006).
13.3.1 2006 Metcon Residual Analysis of the Heaps
Following completion of the two test heaps Metcon was contracted by Castle Gold to carry out an analysis
and reporting of gold distribution by size fraction; comparing head ore samples with leached ore residues
for both heaps (no head sample was collected for Heap 1). Metcon’s summary report for this work
(Iasillo, 2006) can be found in Appendix A as part of the Koningen (2006) report. The results of the
analysis are summarized in Tables 10 and 11.
Table 10. Metcon gold-size fraction distribution of Heap 1 leached ore residue.
Nominal Opening
(inches)
Weight Distribution
(%)
Heap 1 (Low Grade Ore) Leached Ore Residue
Assay
(g/t)
Gold
Distribution
(%)
5.0 4.5 0.39 15.0
-5 +1¾ 7.0 0.28 16.8
+1¾ +¾ 11.2 0.17 16.6
-¾ 77.3 0.08 51.6
Totals 100 100
Average Grade 0.12
Table 11. Metcon gold-size fraction distribution of Heap 2 head ore and leached ore residue.
Nominal Opening
(inches)
Weight Distribution
(%)
Heap 2 (High Grade Ore) Head Ore Sample
Assay
(g/t)
Gold
Distribution
(%)
5.0 10.0 1.43 8.0
-5 +1¾ 19.6 1.39 15.3
+1¾ +¾ 10.2 1.73 9.9
-¾ 60.2 1.98 66.8
Totals 100 100
Average Grade 1.78
Heap 2 (High Grade Ore) Leached Ore Residue
5.0 6.8 1.99 16.0
-5 +1¾ 19.0 1.34 30.3
+1¾ +¾ 15.4 0.91 18.7
-¾ 58.8 0.53 31.0
Totals 100 100
Average Grade 0.84
13.3.1.1 Heap 1 Analysis
For Heap 1, the calculated average gold grade is 0.12 g/t Au. Combining this with the carbon stripping
records yielded a calculated head grade for Heap 1 of 0.25 g/t Au and an ultimate gold recovery of 51.7%.
From Heap 1’s distribution of gold by size fraction, Koningen (2006) concluded that it is reasonable to
expect that if all of the +¾” material were crushed to