Cost of Mineral per oz.:
El Limon, located near the town of Zaragoza, Colombia, is a high-grade gold mine and mill, currently producing gold an estimated cost of $700/oz.
Para Resources recently completed an upgrade program at El Limon, increasing the mill capacity to 100tpd and putting the infrastructure in place to increase production to 200tpd at a later date. Nearly 60 independent gold mining operations are located in very close proximity to the El Limon production facility, which represents very strong toll milling potential for the company.
In the area there are two zones of metamorphic rocks, one of feldespathic-aluminic gneisses and the other associated to the Cajamarca Complex rocks. There are also granitic bodies associated to Cretaceous magmatism.
Gneisses and schists occur in bundles which are elongated in an N-S course; they cover the entire area and they are intruded into the NW by a stock of granodioritic composition and small dikes of porphyry andesitic composition.
The area features Quaternary deposits; the largest ones are located on the creeks called Juan Vara, Sardina and Culebra.
The main structure present in the area is the Otu Fault that crosses the area from North to South, the control over the Juan Vara creek is relevant.
The known vein systems of the region extend up to 2-3 km in length with plunging high-grade ore shoots central to the vein and surrounded by a lower grade halo. Vein dips are typically around 30-40°, and occasionally sub-vertical.
The mineralization of El Limon mine is embedded in the quartz-feldespathic gneisses. The gold occurs in a milky quartz vein, to the west of Otu Fault, its approximate course is N10E/40W, with average thickness of 0.40 m. These features are very consistent in an extension of almost 400m on the course and 350m in the dip direction.
Typical production grades of the region range 8-12 g/t Au diluted. However, higher-grade mines also exist, such as Quintana and El Limon mines at 15-20 g/t Au diluted. Vein widths are typically below 1m, although both the hanging wall and footwall zones can contain appreciable economic mineralization within the high-grade cores.
Structure is continuous, except for a series of reverse faults, with displacements ranging from 0.2 up to 40 and 60 meters, of which the main ones are El Limon and Leonel Faults, and to the north the 5N and the Victoria faults.
Gold mineralization is related to sulphide contents, mainly pyrite, with smaller amounts of galena, sphalerite and tetrahedrite, usually occurring as clear strips with a thickness ranging from 2 to 5 mm, and they comprise from 7% to 12% in volume. Occasionally the strip structure is replaced by distributions of sulfides which are more irregular or uneven.
Pyrite is the first most common and abundant ore, present in the form of aggregates of anhedral and subhedral crystals.Tetrahedrite is the second most abundant ore; usually it occurs in anhedral crystals. Gold is the most important metal; it appears in the form of grains in native state or electrum, normally encapsulated with galena and in the form of inclusions in pyrite crystals, but not always. The particle size is distributed in ranges from 1 to 120 microns, occasionally above 200 microns.
Gold – silver ratio is 1:1.2; the mineralization is normally contained within quartz veins, it is very rare to find quantities of gold directly in the host rock. The tenor of gold appears to relate to the quantity of sulphides, preferably related to the presence of sphalerite and galena.
Photographs taken during site visit May 2016: