Transatlantic is earning into the historic Miller Gold Property by means of a gold production royalty near Helena, Montana.
A historical Report on the Miller Mine notes that historically, gold bearing ore was mined on a small scale by individual owners with sporadic production between 1901 and 1948. The mine is being re accessed by Transatlantic to review existing ground conditions and infrastructure.
Located at the top end of the Confederate Gulch near what is now a ghost town in Diamond City where it once had a population of 10,000. Placer gold was abundant in the region.
- Miller had an average recovered grade mined of 7.94 Oz /ton Au (248 g/t Au ) and 4.65 Oz /ton Ag ( 145 g/t Ag)
- A Hole #1 was drilled 300 feet below the lowest recorded workings and recorded 14.7 Oz /ton Au (516 g/t Au)
The Miller Mine mineralization occurs in quartz veins within and on the contact of a quartz diorite stockwork. The discrete veins dip 30 degrees whilst the stockwork has multiple veinlets that range in width from a few cms to 2 metres. The contact zone of alteration has been noted as over 15 m wide ( 50 feet ). Mining has been undertaken on both an open cut and underground methodology near surface.
The mine areas is at an elevation of 2000 m ( 6650 Feet)
Location
Miller Mine is located in northern Broadwater County of Montana approximately 40 miles east south east from Helena , Montana
The District setting is that the Miller Mountain forms the south western flank of the Big Belt Mountains with a trend north east south west.
The rock in the region consists of primarily sediment and igneous intrusives. The pre Cambrian Newland Limestone is estimated to be 1.6 km thick ( 5,000 ft) and dips from 40 to 80 degrees intruded by an Early Tertiary quartz monzonite and quartz diorite.
The major alteration is silicification and quartz veining over a known the 1.5 km ( 4,400 feet) formed under a gentle anticline. The mineralisation appears primarily on the contact of the igneous and sedimentary rocks with gold free in veins and with pyrite as well as disseminations throughout the stockwork. The mineralisation in general is associated to the pyrite and to a less of an effect chalcopyrite , galena and sphalerite.
All the ore deposits in the district lie on the contact of the igneous and sedimentary package and where weathered into the Gulch providing a large amount of alluvial placer gold historically.
Historical Development
The Mineralised outcrop at the surface represented the commencement of mining on a knoll at 6,800 feet with the earliest worked known as 1900 , and mined sporadically between the family and its owners to a large majority until 1954.
The mineralisation was accessed by 4 Adits as well as minor surface open pit works with limited survey information. The # 4 level is 300 feet below the lowest workings with a more recent cross cut commenced on the Jonnie Gulch following in on hole number 1 drilled in 1968.
Miller Known Strike = 500 m
Known Depth = 200 m
Historic Widths = 0.2 to 2.5 m
The Miller Vein is considered the primary production target on the Property , though a larger halo of low grade stock work in the granodiorite is an additional target.
The Miller mine development extends over 100 m ( 300 Feet) below surface level, with a series of 4 drifts on the vein. The # 4 Lower Level has been more recently accessed by Transatlantic with high grades above 15 g/t Au having been received.
Source: Report on the Miller Mine ,Helena (1969, Fred Hemsworth)
Next Steps
Transatlantic recently completed an underground sampling of the vein and has planned to drill the down dip expression of the vein and geological contacts.
Rehabilitation of the underground workings will permit cost-effective exploration of veins from underground in order to develop mineral resource and expedite development of the project.