Thunder Gold Corp. Announces Initial Metallurgical Results for Tower Mountain near Geraldton
Thunder Gold Corp. is pleased to announce initial metallurgical results from the Tower Mountain Gold Property near Thunder Bay, ON; encouraging reconnaissance exploration results at the PEN Property near Geraldton, ON; and the acquisition, through staking, of an additional 106 cells (2,189 ha) extending the PEN property to the east.
TOWER MOUNTAIN PROPERTY
Metallurgical Test Results
Bureau Veritas Minerals - Metallurgical Division, Richmond B.C ("BV"). completed initial metallurgical testing of half drill core samples from the Tower Mountain property. Twelve (12) representative half core samples were submitted for initial bottle roll testing to determine the metallurgical recovery of the Tower Mountain mineralization. In addition, standard bond work index and acid-based accounting tests were completed to determine the hardness of the mineralization and evaluate the acid-generating potential of the Tower Mountain mineralization.
The half core samples ranged in grade from 0.295 g/t Au to 1.07 g/t Au. Samples were selected throughout the known mineralization, at different depths and from different grade ranges. A 2.0 kg aliquot (P80 ~ 75 µm) was leached in a 1.0 gram sodium cyanide (NaCN) per litre of solution (40% solids by weight) for 72 hours. Calculated recoveries ranged from a low of 72.5% to a high of 94.9% and averaged 86.8% for the twelve samples tested. Residual gold grades ranged from 0.03 g/t Au to 0.43 g/t Au (Ref. Table 1.0). BV noted that gold leached rapidly in the first 8 hours and was largely complete after 24 hours. They noted no correlation between gold grade and gold recovery. BV indicated that gold recoveries in the low 90's are reasonable and recommended additional metallurgical testing to optimize gold recovery.
Standard bond work index tests, at a closing screen of 106 µm, indicate a Bond Work Index of ~20 W (kWh/tonne).
Acid-Based Accounting ("ABA") of the leach tailings were completed to determine the acid-generating potential of the tailings. The ABA testing indicated that two of the twelve samples tested were potentially acid-generating however, the entire twelve sample suite returned a Neutralization Potential of 76.5 indicating that the entire population is not acid-generating.
Wes Hanson P.Geo., CEO of Thunder Gold notes: "The initial metallurgical test work indicates that the mineralization at Tower Mountain is amenable to direct cyanidation with estimated recoveries of more than 90%. ABA testing indicates the mineralization is not acid-generating. The results assist us in defining conceptual goal posts to guide future exploration at Tower Mountain. Our geological team has been re-logging the historical core (2004-2011) to standardize nomenclature in advance of litho-structural interpretation. The goal is to identify potential controls of the higher-grade mineralization within the broad, low-grade halo that extends to the west for 500 meters from the Tower Mountain Intrusive Complex. The re-logging confirms higher gold grades occur within and immediately adjacent to, intrusive dikes and sills emplaced in the volcanic rocks surrounding the Tower Mountain Intrusion. Extensive zones of brecciation, that are strongly propylitic altered, typically return higher gold grades, especially when cut by later intrusive dikes and sills. Re-logging has identified at least two phases of the intrusion to be gold enriched, suggesting potential to define additional mineralization within the intrusion itself, and significantly increasing the exploration target area for follow-up drilling in the future.
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