Guadalupe de Los Reyes project drill results
Northern Crown Mines Ltd NCW
Shares issued 18,072,141 Nov 25 close $0.45
Wed 26 Nov 97 News Release
Mr John Brock reports
Tonnage and grade calculations for three previous metals deposits within
Northern Crown's Guadalupe de Los Reyes project indicate a contained
758,000 ounces gold and 15.9 million ounces silver.
The large 88 sq km project includes former producing gold and silver mines
25km by road southeast of the town of Cosala in Sinaloa State, Mexico.
Tonnage and grade calculations are based on fire assays from 375 reverse
circulation drill holes. Standard geologic modeling and kriging methods
were employed using cut-off grades of 0.5 grams gold per tonne for
mineralization positioned for open-pit extraction and from 1.0 to 1.5 grams
gold per tonne for mineralization holding promise for underground mining.
Additional exploration potential has not formed part of the calculations.
The following table summarizes grade calculations:
Au Ag
Zone (g/T) (g/T)
Zapote-Tahonitas
Zapote 1.36 8.7
Tahonitas 1.46 49.8
Subtotal 1.37 13.1
Chiripa-San Miguel-
Noche Buena
Chiripa-San Miguel
underground 3.79 91.0
Noche Buena 1.15 24.5
Subtotal 2.24 51.8
Guadalupe Mine Zone
Laija underground 3.94 134.6
West 1.38 26.1
Subtotal 2.95 92.5
Project Total 1.94 40.7
Zapote/Tahonitas
The Zapote deposit is the focus of a preliminary feasibility study based on
197 holes drilled at 25m centres over a length of 1,000m and a width of
150m. Independent engineering firms, Steffen, Robertson and Kirsten
(Canada) and Minorex Consulting, have assisted the company in preparation
of tonnage and grade calculations that will form the basis of the
pre-feasibility study currently in progress. The study, being produced by
Pincock Allen and Holt, should be completed by year-end. An initial
open-pit mine plan with a heap leach processing facility is contemplated,
with higher grade zones at depth to be later mined from underground. With
only 33 holes drilled to date on the adjacent 1,000m long Tahonitas zone,
additional drilling is expected to be recommended for inclusion of
Tahonitas mineralization in the final Zapote mine plan.
Guadalupe Mine Zone
The 2,500m long Guadalupe mine zone has been partially explored with 78
holes defining 800m of strike length at the central Laija zone and 200m at
the West zone. The Laija holds opportunity for both open pit and
underground mining with 1.8 million tonnes grading nearly four grams gold
and 135 grams silver using a 1.5 grams cut-off. The West zone, if
considered for open pit potential, contains 1.1 million tonnes grading 1.4
grams gold and 26 grams silver at a 0.5 gram per tonne gold cut-off.
The overall Guadalupe Mine zone, as drilled to date, contains a calculated
4.8 million tonnes grading 2.15 grams gold and 69 grams silver per tonne,
using a 0.5 gram gold cut-off. The drill-defined portions of the zone
remain open and warrant additional drilling. Scoping and mining
optimization studies are planned in order to classify mineralization
amenable to both open pit and underground mining plans.
Chiripa-San Miguel-Noche Buena
Drilling of 33 holes along 1,000m at San Miguel-Chiripa and 25 holes along
350m at Noche Buena is defining gold-silver mineralization in both open pit
and underground configurations. The Chiripa-San Miguel zones consist of
steeply dipping vein-stockwork zones that vary in thickness from three to
20m and remain open beyond the drill tested depth of approximately 100m.
Using a 1.00 gram gold cut-off, 1.1 million tonnes was calculated grading
3.79 grams gold and 91.0 grams silver. Several recently discovered
connecting branching structures present high grade targets for continued
exploration. One such structure was tested by three holes that had a
weighted average of 4.71 grams per tonne gold and 316.0 grams per tonne
silver over 6.1m. The three to 36m thick Noche Buena zone dip slopes along
the hillside and presents an open pit target where calculations based on a
0.5 gram gold cut-off indicate 1.6 million tonnes grading 1.15 grams per
tonne gold and 24.5 grams per tonne silver.
In summary, drilling of three zones on the Guadalupe de Los Reyes property
has outlined geological potential for 758,000 ounces of gold and 15.9
million ounces of silver of which approximately half is within reach of
open pit configuration. The silver content has an in-ground value
equivalent to 280,000 ounces gold at current precious metals prices.
The company is planning a program of diamond drilling and reverse
circulation drilling in 1998 in order to define additional tonnage and
grade within areas of known mineralization as well as for high grade
bonanza gold mineralization that may remain to be identified at depth
within the project area.
Based on widely-spaced exploratory drilling to date and historic mining
records, the company believes that additional potential in the range of
500,000 ounces gold remains within the areas of known mineralization.
Further blue sky opportunity below 200m from surface at the Guadalupe mine
zone and along the 5km El Orito zone also will be drilled.
Contingent on receipt of a positive preliminary feasibility study,
management will, subject to financing, move directly to bankable
feasibility for the Zapote deposit early in the New Year. |
