- Los Azules
Introduction
The Los Azules property, located 800 kilometers north of Santiago, covers the historic Los Azules high grade oxide copper-gold mining district and is readily accessible by paved and good gravel road from the city of Copiapó sixty kilometers to the west.
Claims & Ownership
The property consists of 22 exploration and 3 exploitation concessions totaling 6,568 hectares owned by Polar Star and 5 exploitation concessions totaling 790 hectares owned by local miners. Polar Star holds an option to purchase agreement with the local miners whereby it can purchase a 100% interest in their properties by making staged payments totaling US$1.75 million over the next four years.
Property Geology
The property is underlain by a generally sub-horizontal sequence of sub-areal epiclastic sediments and inter-bedded basaltic to andesitic flows within the Late Cretaceous – Paleocene Cu-Au Metallogenic Belt of the Chilean pre-Cordilleran. Numerous post-magmatic hydrothermal collapse breccia pipes cut these sediments and are distributed in clusters throughout the property. The individual pipes, which are circular to elliptical in plan, range from 5 m to 350 m in diameter. On the property at least four are over several hundred metres in diameter. About 100 of these pipes have previously been recognized in the Los Azules District.
Mineralization
The hydrothermal mineralization of the pipes may be divided into an early fragment replacement stage, followed by open-space filling. The filling stage consists of tourmaline, accompanied by specularite and followed principally by quartz, chalcopyrite, pyrite (+/- gold), moly and galena. All the Azules pipes appear to contain uranium however no uranium minerals have been identified to date. A zone of surface oxidation up to 100 m deep has produced a blanked of readily leachable copper minerals including atacarmite, chrysocola, brocanthite, copper wad and copper pitch.
Exploration History
There are no records of recent systematic exploration in the property area however small scale mining has been carried out in the larger pipes since at least the 1930’s when ever copper prices permitted. Currently two of the larger breccias are being mined by piquineros on a small scale, about 250-350 tonnes per month, for copper oxide in the 3-5% range. However, the average copper grade for the breccias is estimated to be in the 0.7-1.0% range. During Polar Star’s June-July 2007 visits the larger pipes were checked for uranium using the Exploranium GS135 gamma ray spectrometer. All the breccias tested are uraniferous consistently recording values of over 100 ppm up to 550 ppm (1.2 lbs) U.
Top