Remhoogte/Holsloot Project

Remhoogte/Holsloot Mine Location

Background

The 2,634 hectare Remhoogte/Holsloot Project was acquired by Rockwell at the end of May 2015. The Project is located in the Hay district of the Northern Cape Province of South Africa approximately 195km southwest of Kimberley. The operations are located on Remhoogte 152 (1,585ha) and Holsloot 47 (1,049ha). It is contiguous to Rockwell’s other properties in the Middle Orange River.

Geology

The bedrock on both Remhoogte and Holsloot is Dwyka shales. The gravel terrace has been described as a high-level “A” terrace. Both colluvial and fluvial-alluvial gravel units are known to exist on the Remhoogte and Holsloot properties. Little is known currently regarding the composition of the gravel units or their distribution patterns.

Processing Plant

There are three processing plants at the Remhoogte/Holsloot Project that have a maximum total monthly processing capacity of approximately 200,000 m3. At Remhoogte, a processing plant was commissioned in June 2014 from all-new equipment, consisting of a Bourevestnik Bulk X-ray system for the processing of coarse gravels and a four rotary pan plant to treat the fine gravels. A second rotary pan plant at Remhoogte consisting of four pans was commissioned on the property in November 2014. At Holsloot, a processing plant was recently commissioned from new equipment and consists of a de-sanding system, a Bourevestnik Bulk X-ray system for the processing of coarse gravels and a dense media separation system for fine gravels. During the integration of the Remhoogte/Holsloot Project into Rockwell’s MOR operating model, the Company is operating the plants at a throughput rate of 120,000m3 per month.

Remhoogte Plant 1

Ore preparation Ore Enrichment Final/Recon recovery machines
Finley Screen De-sanding Screen Scrubber DMS Coarse BV Mids BV Flow Sort Machine
4 x 200 tph 2 x 100 tph 1 x 150 tph 1 x 35 tph 1 x 80 tph 1 x 50 tph 12x (17tph total)

 

Remhoogte Plant 2

Ore preparation Ore Enrichment Final/Recon recovery machines
Finley Screen Pans BV Bulk Sorters Flow Sort Machine VE Recovery Machine
4 x 200 tph 4 x 50 tph 12x (17tph total)

 

Holsloot Plant

Ore preparation Ore Enrichment Final/Recon recovery machines
Finley Screen De-sanding Screen Scrubber DMS Coarse BV Mids BV BV SPS
4 x 200 tph 2 x 100 tph 1 x 150 tph 1 x 35 tph 4 x 200 tph 1 x 80 tph 2 x 3 tph

 

Mining

Mining operations are currently only of deflated gravels, Rooikoppie gravels. These gravels are situated on the surface so no drilling or blasting is required. The vegetation that covers these is cleaned off by means of Bulldozer or tyre dozer. Once the prospective mining area has been cleaned the Rooikoppie gravel is pushed by means of bulldozer into windrows 50m apart. The 50m distance is chosen in order to minimize the distance which the bull dozer has to push. Once the dozing is completed and the areas are clean, further cleaning of the underlying undulating calcrete is required. Due to weathering of the calcrete, pockets (makondo) are created within which the Rooikoppie gravel gravitationally migrates downwards. The cleaning is done by means of smaller dedicated kit that cleans out the pockets and creates makondo stockpile which is transported to the in-field screen to be screened. The in-pit mobile screens are used for screening off the fines and coarse material which will be transported to the rehabilitation areas. The in-pit screens are feed from the windrow stockpile using excavators. These screens are mobile, thus they are moved to the windrow stockpiles. The screened product is then loaded onto the 100T trucks by means of loaders. The product is taken to the plant; each of these plants has a different processing method; Remhoogte 1 coarse BV and rotary pans with a pan BV, Remhoogte 2 has rotary pans with concentrate being stockpiled in concentrate bins due to no final recovery on this plant, Holsloot plant has a fines DMS which feeds into BV final recovery and a coarse BV to process the coarse fractions. Once processing has been completed the tailings are transported back to the current mining areas by articulated dump trucks. A tyre dozer or bulldozer is used to flatten the rehabilitation areas.

Download the Technical Reports

wt1

Remhoogte/Holsloot Resource Summary June 2015

wt2

Revised Technical Report on the Remhoogte/Holsloot Diamond Mine