March 8, 2017

Geology

Golden Reef Mining (GRM) is a Zimbabwean Mining and Exploration Company with interests in Precious and Base metals. Currently, the company is operating two Gold projects at Ruia Mine in Mt Darwin and Felixburg Mine in Gutu (figure 1).  The company is also operating two Chrome projects at Mutorashanga and Lalapansi (figure 1).

Figure 1-GRM Properties

 

GOLD

RUIA MINE

       LOCATION AND ACCESS

Ruia Gold Mine is wholly owned by Golden Reef Mining Pvt Ltd. The project is located in Mt Darwin some 170 km North of Harare. Access to the project is via a nice tarred road to Mt Darwin from Harare via Bindura.  From Mt Darwin one turns left into Matepatepa road and drive for 13km due west

CLAIMS HOLDING

A total of 1273 ha around Ruia Mine comprising of:

20 blocks of Gold Claims

5 Ordinary Base Metal Claims

7 Special Base Metal Claims

REGIONAL GEOLOGY

Geologically the area lies within the narrow Mt Darwin Schist belt which is comprised of Mica Schist, Banded Ironstone and Greenstone Schist. These were intruded by dolerites, felsites, serpentinite and quartz. The Greenstone Schist are metamorphosed basic igneous rocks mainly of volcanic origin. Some are of intrusive origin composed of ancient dolerites. The quartz sericite schist range from quartz porphyries to highly fissile sericite schist. The schist belt is bound to the north and south by granites.

MINERALIZATION

Ruia Mine is a low grade high tonnage deposit which is being exploited by open pit mining and the ore is processed through heap leaching. Mineralization is restricted to a wide shear zone approximately 60m composed of feldspar porphyry and mica schists. Gold mineralisation is associated with the sulphide species pyrite, arsenopyrite, malachite and minor chalcopyrite.

 EXPLORATION

  • The Ruia Gold  Prospect  is  a  result  of  exploration  work  undertaken  by  Cluff  Resources during the period 1988 to 1989 under Exclusive Prospecting Order 609.
  • Subsequently, a low-grade oxide resource of approximately 1.2 million tonnes averaging 1.25 Au g/t   was outlined and the Ruia prospect was pegged and registered as Bechanis 517130.
  • Golden Reef Mining took over the area in 2011 and initiated a sampling program around the trenches and artisanal miners’ workings.
  • RC drilling was done in 2011 which resulted in the drilling of two holes totalling 100m.
  • In 2016 Golden Reef Mining undertook a second phase of RC Drilling where 29 holes were drilled totalling 1386m. The exercise covered a strike length of 468m.
  • A drill indicated resource of 3.4 Million tonnes at 0.83 g/t Au was declared from RC drilling. The total gold content was estimated at 98 165 ounces.
  • A diamond drilling campaign was undertaken by Golden Reef Mine at Ruia Mine from November 2016 to January 2017.
  • 15 diamond drill holes totalling 1457m were drilled during the first phase. The total resource estimation from this drilling is summarised in table 1 below.

RUIA MINERAL RESOURCES AS AT 30 MAY 2017

 

2.0 FELIXBURG

2.1 LOCATION AND ACCESS

The mining area is located some 200km south of Harare near Mvuma in the Masvingo Mining district-see figure 1. The place is easily accessible by the main Masvingo-Harare highway and only the last 10km are by an all-weather dust road.

 

2.2 CLAIMS HOLDING

A total of 110 ha around Felixburg comprising of:

  • 11 blocks of Gold Claims

2.3 REGIONAL GEOLOGY

The goldfield consists of an east-west belt of basement schists from 1.6km to 8km wide and some 11km long, bounded to the north and south by granite intrusions. Sandy Karroo beds overlie the granite and schists to the north.

The rocks of the schist belt are mainly of the Greenstone series, fine grained epidiorites and greenstone schist- biotite and actinolite schists. A belt of banded ironstones follows to the southern granite/schist contact-see figure 2. The general strike of the schists is east-west, with steep southerly dip.

Figure 2- Map showing the geology of Felixburg

  MINERALISATION

The mines were worked during the 1930’s and recent workings were limited to dump retreatment and artisanal workings.  These claims are highly prospective taking into account the high grades which vary from 6g/t to 10.22 g/t, with earlier work revealing grades as high as 36g/t in some places, and the limited mining which took place (developed to second level -60m).

The minerals present reported to be in the quartz are pyrite, galena and gold. The pyrites and galena are both sparsely disseminated in the quartz and the gold is in discrete grains often the only visible metallic constituent in the rock. The gold is reported to be free-milling, generally quite coarse and remarkably pure.

There are two types of quartz present: in the master fault planes the quartz is a dark grey to grey-blue colour, whereas in the secondary oblique fissures carry white quartz. Both types carry high gold content.

2.5 MINERAL RESOURCES -DUMPS

2.5.1 FELIXBURG MINERAL RESOURCE AS AT 30 MAY 2017

Dump No. Tonnage Grade (g/t) Gold Content (kg)
Dump No. 1 110,000 0.7 77
Dump No.2 100,000 0.3 30
Dump No.3 55,000 0.6 33
Dump No.4 15,000 1.1 16.5
Dump No.5 20,000 1.9 38
Total 300,000 0.67 201

 

The picture below shows the dump resources at Felixburg.

Figure 3- Dump Resource at Welcome claims

 

2.5.2   MINERAL RESOURCES – RUN OF MINE (ROM)

There has not been any systematic mineral resource delineation during the days when the mines were operational. The available data indicates a potential of over one million ounces as contained in a report by Dr. J.W.N. Sharpe of 1963 (pgs 145-154). He visualized 400,000 tons for every 150m vertically and from 5,000 – 10,000 ounces of gold per month on an output ranging between 6,000 to 10,000 tons of ore per month.

There is potential of sulphide ore underground from the existing underground workings at Welcome, Tichargwa, Help Mekaar and Castle claims. Exploration diamond drilling to delineate this underground resource is underway.

 CHROME

BLACK SANDS RESOURCES (BSR)

BSR is the chrome division of GRM which specialises in chrome mining. Currently it operates an eluvial chrome mining and processing plant in Lalapansi and claims in Mutorashanga.

LALAPANZI

LOCATION AND ACCESS

Access to the project is via the Gweru-Shurugwi road for 18km to Guinea Fowl school then turn east for some 20 km. The project is located on the eastern flank of the Great Dyke.

 CLAIMS HOLDING

A total of 75 ha around the Valley area comprising of:

3 Ordinary base metal Claims-see figure 3.


Figure 3 –Lalapanzi chrome blocks

 GEOLOGY

Eluvial chrome deposits in soil or rubble are derived from the breakdown of chrome ore bodies (seams) or from the breakdown of ultramafic rocks (serpentinites and pyroxenites) containing disseminated accessory chromite in the Great Dyke.

The chromite in the eluvial deposit was formed by deposition of eluvial chromite along valleys. The deposition is prolific along the V-shaped valleys compared to the U-shaped valleys owing to the fact that the gradient is less and the deposits are less likely to be eroded during heavy down pours.

MINING AND PROCESSING

The mining operations are done using excavators, which scoop the topmost soil up to a depth of approximately 1m. This is the area where eluvial chrome is concentrated. The ore is transported to the washing plant, with the furthest mining site being 2km away from the plant.

The processing of the chrome concentrate is done at the washing plant. This involves channelling the ore into the plant through a conveyer. The ore is mixed with water, and churned and allowed to pass through spirals, which separate particles of different densities by gravity.

Chrome concentrate is separated with soil and water and collected on the ground surface-see figure 4

Figure 4- Chrome Washing plant

 

MINERAL RESOURCES

The Lalapanzi claims has an indicated eluvial resource of 5 million tonnes insitu ore containing 12.5% Cr2O3 fines.

 MUTORASHANGA

LOCATION AND ACCESS

The Mutorashanga claims are located on Cairnsmore Estate about 100km to the north of Harare. Access to the area is via the Mazowe Mvurwi road.

CLAIMS HOLDING

Area covering 100 ha comprising of:

Four ordinary base metal claims – see figure 5.

       Figure 5 – Mutorashanga base metal claims

 REGIONAL GEOLOGY

Eluvial chrome deposits in soil or rubble are derived from the breakdown of chrome ore bodies (seams) or from the breakdown of ultramafic rocks (serpentinites and pyroxenites) containing disseminated accessory chromite in the Great Dyke.

The Mutorashanga eluvial claims are located along the eastern flanks of the Great dyke in the Cairnsmore Estate-see figure 6. The chromite in the eluvial deposit was formed by deposition of eluvial chromite along valleys. The deposition is prolific along the V-shaped valleys compared to the U-shaped valleys owing to the fact that the gradient is less and the deposits are less likely to be eroded during heavy down pours.

 

Figure 6- Mutorashanga geology map

MINERAL RESOURCES

No mineral resources have been delineated. Exploration work to commence in third quarter 2017.

 

MANASA MUJURU

Geologist