Money Rock

Prospect, Active

Alternative names

Money-Rock
Rainbow
Aurora
Indian

Commodities and mineralogy

Main commodities Au
Other commodities As; Bi; Te
Ore minerals arsenopyrite; gold; pyrite
Gangue minerals dolomite; quartz; sericite

Geographic location

Quadrangle map, 1:250,000-scale BD
Quadrangle map, 1:63,360-scale B-2
Latitude 64.4614
Longitude -145.0272
Nearby scientific data Find additional scientific data near this location
Location and accuracy This property consists of three blocks of State of Alaska claims that are contiguous or close by; they cover much of sections 8-10, 16-17, 19-20, and 29-30 of T. 5 S., R. 14 E., of the Fairbanks Meridian. The coordinates are at about the center of the samples with the best gold values. The outlines of the claim boundaries are shown on figure 1 of Schaefer (2006) and Alix Resources Corp. (2010). The claims are about 3 miles northwest of the Pogo Mine (BD033) and about 3 miles west of the junction of Indian Creek and the Goodpaster River. The location is accurate to 500 feet.

Geologic setting

Geologic description

The rocks in the area consist primarily of pre-Mississippian paragneiss and orthogneiss and lesser schist and quartzite; the metamorphic rocks are intruded by several Cretaceous granitic plutons (Werdon and others, 2004). The Aurora claim block is underlain by paragneiss, schist, quartzite and minor orthogneiss that are cut by several Tertiary basaltic dikes. The Indian claim block is mainly underlain by orthogneiss similar to that at the nearby Pogo mine (BD033) and Cretaceous granodiorite of the Goodpaster Batholith to the north. The Rainbow claim block is mainly paragneiss in contact with Cretaceous (96.6-99 Ma) tonalite; hornfels is developed at the contact. The Rainbow claim block is cut by a small Cretaceous(?) granodiorite/quartz monzonite dike that is moderately altered to sericite and carbonate. Locally, the gneiss is moderately to strongly silicified with the development of sericite+/-carbonate (Schaefer, 2006). Airborne geophysical surveys (Burns and others, 2000; 2005) show a strong magnetic anomaly over the hornfels adjacent to the Cretaceous tonalite at the Rainbow claim block; a similar highly magnetic anomaly over the north half of the Aurora claim block suggests hornfels adjacent to a buried intrusive.
Quartz veins with disseminated arsenopyrite have been found in float on the Rainbow claim block near the contact between gneiss and the Cretaceous tonalite (Schaefer, 2006; Alix Resources Corp., 2010). Rock float samples contain up to 2.4 grams of gold per ton and more than 10,000 parts per million arsenic and anomalous bismuth. Scattered soil samples from the area are also generally anomalous in gold and arsenic, and locally anomalous in bismuth and tellurium.
The Rainbow, Aurora, and Indian claim blocks were first located by three prospectors, beginning in 1999. In 2002, they were leased to the Anglo-Gold Corporation who did only limited work, mainly soil sampling on the ridges, as part of a larger effort in the area. In 2006, the claims were leased to Tonogold Resources Inc. (2008). In 2010, the property was held by the Alix Resources Corp. (2010) and in the summer of 2010 they signed an option agreement with the Precious Metals Exploration Company to explore the property.
As of 2012, Alix refers to this property as Money Rock. In summer 2012, Alix performed a two-hole drill program designed to test the subsurface expression of a surface rock and soil gold anomaly. Both drillholes encountered alternating intervals of paragneiss and orthogneiss. Gold in both holes occurs in quartz-arsenopyrite-pyrite veins associated with broad zones of patchy sericite-dolomite-silica alteration. Results from MR-12-01 are 0.48 gram of gold per tonne from 48.0 to 53.0 meters, 0.47 gram of gold per tonne from 111.0 to 112.4 meters, and 1.67 grams of gold per tonne from 199.0 to 200.6 meters. Results from MR-12-02 are 0.53 gram of gold per tonne from 395.3 to 396.8 meters (Alix Resources Corp., 2012a, 2012b).
Geologic map unit (-145.029553562662, 64.4610180650331)
Mineral deposit model Arsenopyrite-gold-quartz veins; polymetallic veins? (Cox and Singer, 1986; model 22c).
Mineral deposit model number 22c?
Age of mineralization May be related to nearby Cretaceous (96.6-99 Ma) plutons (Werdon and others, 2004).
Alteration of deposit Sericite-carbonate-silica alteration with arsenopyrite and other sulfides in veins and as disseminations (Alix Resources Corp., 2012a).

Production and reserves

Workings or exploration
The Rainbow, Aurora, and Indian claim blocks were first located by three prospectors, beginning in 1999. In 2002, they were leased by the Anglo-Gold Corporation who did limited work, mainly soil sampling on the ridges, as part of a larger effort in the area. In 2006, the claims were leased to Tonogold Resources Inc. In 2010, the property was optioned by the Precision Metals Exploration Company from Alix Resources Corp. (2010).
As of 2012, Alix refers to this property as Money Rock. In summer 2012, Alix performed a two-hole drill program designed to test the subsurface expression of a surface rock and soil gold anomaly. Both drillholes encountered alternating intervals of paragneiss and orthogneiss. Gold in both holes occurs in quartz-arsenopyrite-pyrite veins associated with broad zones of patchy sericite-dolomite-silica alteration. Results from MR-12-01 are 0.48 gram of gold per tonne from 48.0 to 53.0 meters, 0.47 gram of gold per tonne from 111.0 to 112.4 meters, and 1.67 grams of gold per tonne from 199.0 to 200.6 meters. Results from MR-12-02 are 0.53 gram of gold per tonne from 395.3 to 396.8 meters (Alix Resources Corp., 2012a, 2012b). Money Rock is currently operated by Aurora Exploration Company (Wright, 2013).
In October 2016, Millrock Resources Inc. announced that, through a series of purchase and option agreements and claim staking, it has assembled a 39,159-acre land position covering high-potential gold targets (ARDF numbers BD054, BD055, and BD060) in the Goodpaster Mining District near the Pogo gold mine (BD033). The claims cover soil geochemical anomalies, many of which are untested. On several sites there are intersections obtained through drilling by prior operators that are anomalous in gold. Millrock conducted core re-logging, surface geologic mapping, and soil and rock sampling in 2016; this work defined a northeast–southwest-trending corridor of anomalous gold values and several east–west-trending quartz vein systems as well as a small low-angle, northwest-dipping quartz vein with similar characteristics to the tabular bodies at Pogo (BD033). Millrock also collected short-wave infrared spectra from both core and surface samples (Athey and Werdon, 2017).
Indication of production None

References

References

Reporters D.J. Grybeck (Contractor, USGS); V.C. Zinno (Alaska Earth Sciences, Inc.); M.B. Werdon (DGGS)
Last report date 8/26/2017