Maricela Project- Mexico
At Radius Gold's Maricela project, geologists have mapped and sampled an epithermal silver & gold mineralized vein system extending approximately 1.5 km long by 300 m wide, within which occurs multiple veins, stockworks and breccias (Figure 1). Vein intersections have exposed widths of up to 25 meters. Radius Gold has collected 576 rock chip samples which returned values from below detection to highs of 12.75 g/t gold and 3780 g/t silver and various continuous chip sampling across the structures which include highlight intervals of:
- 3 m at 4.46 g/t gold and 1335 g/t silver - Baby Gloria Vein
- 6 m at 1.03 g/t gold and 418 g/t silver - Silver Central Vein
- 25.3 m at 0.31 g/t gold and 62 g/t silver - (intersecting veins)
The Maricela property shows no evidence of previous drilling or systematic exploration. The property has a number of small open pits and shafts where historically high grade material was mined in the 1950's and 1960's and shipped to a processing plant in Cananea. The Mexican geological survey conducted a small sampling program (24 samples) in 2000, and since then no significant work has been completed. The Project has excellent infrastructure and good road access.
The Maricela project is located within a prolifically mineralized mining district, 20 km south of the Cananea mine, one of the world's largest open pit copper mines (Figure 2). The Arizona - Sonora porphyry belt is one of the most important centers of copper mineralization on Earth. Spatially and genetically related to this giant porphyry trend are numerous epithermal gold and silver deposits. Silvercrest Metals' Las Chispas discovery is located 50 km south of Maricela. Las Chispas is a low sulphidation epithermal silver and gold deposit estimated to be amongst the highest grade primary silver deposits in the world. Other significant mines within an 80 km radius of Maricela include, Santa Elena silver gold mine (First Majestic Silver), Nacozari copper mine (Groupo Mexico), Mercedes gold mine (Premier Gold Mines), Maria copper mine (Minera Frisco).
The mineralization at Maricela consists of a series of intersecting epithermal vein systems and associated vein stockworks and breccias that have potential for a bulk tonnage open pit deposit as well as high grade underground vein targets. Radius geologists have conducted extensive mapping and rock chip sampling and have found that the system is open for expansion. See Figure 3 for the Maricela Vein system.
The main vein, Virgin de Plata, strikes NW-SE and has been defined for approximately 1 km. Virgin de Plata is intersected by at least 4 veins (striking NE-SW) forming a horse tail structure of intersecting veins. The veins are generally between 1 and 3 m wide of massive quartz with mineralized stockworks and brecciated vein selvages, extending commonly +10 m across the vein zones. At intersections, larger stockwork zones are observed with zones up to 25.3 m grading 0.31 g/t gold and 62 g/t silver. The mineralization type is a low sulphidation silver gold epithermal vein system hosted within an andesite volcanic sequence. The andesite sequence is intruded by a quartz-monzonite porphyry that is exposed just north, and west of the veins in an uplifted block (Figure 4, Figure 5 & Figure 6).
Maricela silver sold geochemistry
Radius completed mapping and collected 567 rock chip samples which range from below detection to 12.75 g/t gold and 3780 g/t silver.
Radius has taken multiple chip channel sample sections across the veins, stockworks and breccias where outcrops allow. Massive quartz veins constitute the higher grades while veinlet breccias in between the veins and in the wall rock are also variably silver and gold mineralized.
Chip channel sample sections on the Maricela vein structures.
Vein zone Width (m) Au (g/t) Ag (g/t) Baby Gloria 3 4.46 1335 Virgin de Plata & Baby Gloria 25.3 0.31 62 Baby Gloria 22 0.15 39 Baby Gloria 5 0.33 127 Baby Gloria 4 1.23 111 Virgin de Plata 6.9 0.34 110 Virgin de Plata 10 0.62 142 El Arco
(9.7 m with 3 m missing in middle)
El Arco 10.5 0.50 105 Central 6 1.03 418 SE 62 0.03 6 North 1 0.53 349 Amarilla 1.5 0.54 494
Geological model and exploration targets
Radius's geological team believes there is potential for both high grade silver gold veins and bulk tonnage lower grade mineralization that could be amenable to open pit mining. Most of the known veins and associated stockworks have observed widths up to 25 m and occur within a tightly spaced area approximately 1 km x 600 m defining an obvious open pit target. As the project has never been drill tested there is also potential to discover high grade vein systems and ore shoots at depth. Drill permitting is underway.
Radius can earn a 100% interest in the project by making staged payments to the private property owner totalling US$1,250,000 over three years with a final payment of US$1,060,000 due at the end of year three. A total of US$30,000 has been paid to date. The owner retains a 1% NSR which Radius can buy back for US$1,000,000. The property agreement covers several mineral concessions (total 155ha).
Quality assurance and quality control
Surface rock samples are acquired by Radius Gold's geologists and trained sampling teams under the supervision of the geologists. Majority of the rock samples consist of chip channels ranging from 0.5 to 3 m. These samples are forwarded to an ISO/IEC accredited ALS Geochemistry laboratory for analysis of Au, Ag and other elements using ALS codes Au-ICP21 and ME-ICP61. Au-ICP21 is a fire assay method with an ICP-AES finish for Au. ME-ICP21 is a 33 multi-element (includes Ag) analysis that uses a four acid-digestion with an ICP-AES finish. For over-limits of Au or Ag, analysis using a fire assay method with gravimetric finish is automatically conducted. Quality control samples (blankets, standards etc.) are included with the field samples at regular intervals. The QA samples' results are monitored to ensure the returned results are within the acceptable range.