Overview
Status | Care and Maintenance |
Mine Type | Open Pit |
Commodities |
|
Mining Method |
|
Processing |
- Dense media separation
- X-Ray sorting
|
Mine Life | 3 years (as of Jan 1, 2016) |
Operations at Bloeddrif Mine ceased in May 2017. |
Company | Interest | Ownership |
Lower Orange River Diamonds Proprietary Ltd.
|
100 %
|
Direct
|
Summary:
The basement geology of the Bloeddrif area is dominated by the rocks of the Kaigas Formation, comprising interbedded dolomites, metapelites and arenites. The gravel suites associated with both the proto and meso terraces, characteristic of the Baken area, are also present at Bloeddrif.
The proto-sediments at Bloeddrif are predominantly preserved within two cut-off meanders, named B1 and B2, which are partially surrounded by prominent dolomite hills. These terraces are mid-Miocene in age (19 Ma to 17 Ma). Smaller remnants of proto gravel are also present in deep scour pools, which are generally overlain by younger meso-sediments.
The country rock in the area consists of schist, dolomite and metapelite/arenite, with roughly a north-south strike direction and a dip to the west. The dolomite unit constitutes a line of isolated hills, which played a major role in the preservation of some of the proto deposits.
Gravels at the outlet side of both the B1 and B2 paleo-channels have been removed by mining activities conducted by Octha Diamond Company prior to Trans Hex’s involvement. Octha Diamond Company also excavated a number of large sampling trenches in the B1, B2 and Xarries deposits for which no results are available.
Summary:
Ore is mined using open pit mining methods from
numerous small, localised alluvial gravel resources. Mining is carried out with open pit truck and shovel operations from the diamondiferous gravels after removal of overburden. The general method employed is strip mining. The paleo-channels and terraces which host the diamondiferous gravels vary in width and overburden depth and, as such are subject to varying degrees of continuity for active mining faces. Mining also encompasses rehandling and reprocessing of remnant tailings and stockpiled material.
Processing
- Dense media separation
- X-Ray sorting
Source:
Summary:
Baken and Bloeddrif are fixed process plant operations. The Somiluana Mine and WCR operations all have modular plants that can be moved as the production centres change.
LOR processing operations comprise two washing and concentration plants; the Baken Central Plant (BCP), coupled to the Baken Central Recovery Plant (BCRP) at Baken Mine and a single plant treating fresh gravel and tailings at Bloeddrif.
The BCP was commissioned in 2001 and has a nominal 1,350 tonnes per hour (tph) capacity, also producing a final DMS concentrate. Screened fractions report to the DMS plants, from where DMS sinks report to the BCRP, split into three size fractions before being fed through separate XRay sorting machines, with the X-Ray concentrates gravitating to a secure hand sorting facility.
Recoveries & Grades:
Commodity | Parameter | 2018 | 2017 | 2016 |
Diamond
|
Head Grade, carats/cu.m
| 0.03 | 0.006 | 0.008 |
Production:
Commodity | Units | 2018 | 2017 | 2016 |
Diamond
|
carats
| ......  | 2,641 | 3,538 |
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Operational Metrics:
Metrics | 2016 |
Ore tonnes mined
| 440,000 cu. m |
Stripping / waste ratio
| 2.9 |
Reserves at December 31, 2018:
Category | Tonnage | Commodity | Grade | Contained carats |
Indicated
|
31,072,438 cu. m
|
Diamond
|
0.0053 carats/cu.m
|
163,197 carats
|
Inferred
|
20,600,548 cu. m
|
Diamond
|
0.0044 carats/cu.m
|
84,972 carats
|
Operating Costs:
| Units | 2016 |
OP mining costs ($/t mined)
|
ZAR
| 102 |
Processing costs ($/t milled)
|
ZAR
| ......  |
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Financials:
| Units | 2016 | 2015 |
Capital expenditures
|
M ZAR
| ......  |
10
|
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Staff:
Total Workforce | Year |
|
2016
|
Corporate Filings & Presentations:
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Aerial view:
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