Our Mines

Our portfolio incorporates major underground pipe mines and a large high-volume open cast mine

  • Finsch

    Finsch is a world-class mine which benefits from top quality infrastructure, including a modern processing plant

  • Finsch

    Finsch is a world-class mine which benefits from top quality infrastructure, including a modern processing plant

  • Finsch

    Finsch is a world-class mine which benefits from top quality infrastructure, including a modern processing plant


Finsch is one of the world’s significant diamond mines and South Africa’s second largest diamond operation by production (after De Beers’ Venetia mine). The mine benefits from state-of-the-art mining infrastructure, including a modern processing plant which was upgraded shortly before Petra acquired it at a total cost of approximately US$100 million.

Finsch is a major producer, having supplied over 130 million carats in its 40 plus year life to date. Petra is currently implementing a development plan to lift production from 1.6 million ROM carats per annum in FY 2016 to ca. 2.0 million ROM carats per annum by FY 2018.

Finsch has produced large, special diamonds in its history and produces a number of +50 carat stones annually. In addition, the mine is known for highly commercial goods of +5 carats and is rich in gem quality smaller diamonds.


Key Facts

Location Northern Cape Province, South Africa
Size of kimberlite pipe at surface 18ha
Mine start date 1967
Acquisition by Petra Diamonds September 2011
Acquisition cost ZAR 1.425bn
Ownership Petra Diamonds Limited: 74%1
Kago Diamonds (Pty) Ltd: 14%
Itumeleng Petra Diamonds Employee Trust: 12%
Total Resources
(inclusive of Reserves)
49.07 Mcts
Current depth of Resources 1,000m
Mining Method Block cave and sub level cave
Depth of current mining 630m
Mine Plan To 2030
Potential Mine Life +25 years

 1. Refer to Petra’s ‘Effective Interest in Mines’ in the following document: Analyst Guidance Explanatory Notes.


The Finsch kimberlite was discovered in 1960 and the mine was officially opened in 1967. Ore extraction was initially from the open pit. Sinking of the main shaft to access the mine from underground started in 1978. Two vertical shaft complexes, tunnels and ground handling infrastructure were prepared for the continuing exploitation of the pipe with the use of highly mechanised mining methods. In 2008 the treatment plant was upgraded at a cost of approximately US$100 million. On 14 September 2011, Petra purchased Finsch as a fully-staffed, operating mine from De Beers.

Finsch is known for highly commercial goods of +5 carats and is rich in gem quality smaller diamonds. Large, special diamonds are also a feature of the orebody, with a number of +50 carat stones recovered at the mine annually, and the mine also produces very rare fancy yellow diamonds.

Reserves & Resources

Category Tonnes (millions) Grade (cpht) Contained Diamonds (Mcts)
Probable 43.3 57.7 24.96
Sub-total 43.3 57.7 24.96
Indicated 38.9 68.9 26.82
Inferred 39.3 56.6 22.25
Sub-total 78.2 61.7 49.07

1. Resource bottom cut-off: 1.0mm.
2. Reserve bottom cut-off: 1.0mm.
3. Block 4 Resource tonnes and grade are based on block cave depletion modelling and include external waste. The Block 4 PCBC Model was recalibrated to January 2016 pit scans in order to provide an updated estimation of block 4 grade and tonnes.
4. Block 5 Resource stated as in situ.
5. Block 5 Reserves are based on PCSLC and PCBC simulations, depleted for SLC development tonnes.
6. Portion of overburden dumps elevated to Inferred Resource based on sampling programme.

FY 2016 Results

Unit FY 2016 FY 2015 Variance
Revenue US$m 186.4 185.4 +1%
Diamonds sold Carats 2,085,123 2,067,933 +1%
Average price per carat US$ 89 90 -1%
ROM Production
Tonnes treated Tonnes 3,547,798 3,016,385 +18%
Diamonds produced Carats 1,572,725 1,298,914 +21%
Grade1 Cpht 44.3 43.1 +3%
Tailings Production
Tonnes treated Tonnes 2,295,918 2,656,471 -14%
Diamonds produced Carats 641,339 766,960 -16%
Grade1 Cpht 27.9 28.9 -4%
Total Production
Tonnes treated Tonnes 5,843,716 5,672,856 +3%
Diamonds produced Carats 2,214,064 2,065,875 +7%
On-mine cash cost per tonne treated ZAR 183 164 +12%
Expansion Capex US$m 56.5 65.1 -13%
Sustaining Capex US$m 6.7 16.1 -58%
Borrowing Costs Capitalised US$m 10.6 6.8 +56%
Total Capex US$m 73.8 88.0 -16%

1. The Company is not able to precisely measure the ROM / tailings grade split because ore from both sources is processed through the same plant; the Company therefore back-calculates the grade with reference to resource grades.

Production increased 7% to 2,214,064 carats (FY 2015: 2,065,875 carats), mainly due to an increase in ROM tonnes and ROM grades, partially offset by a reduction in tailings tonnes and grades.

The capital programme delivered first production from the Block 5 SLC during Q4 FY 2016.

Mine Plan

Petra is currently implementing a development plan to lift production from 1.3 million ROM carats per annum to ca. 2 million ROM carats per annum by FY 2018. Our initial mine plan extends to 2030, but resources in Block 6 and the adjacent Precursor kimberlite, which sits next to the main body of the Finsch kimberlite pipe, are expected to prolong the actual life of mine for considerably longer.

Production is currently entirely from Block 4 on the 630 mL, which is a mature block that has been largely mined out, resulting in the ore being heavily diluted with waste rock. Subsequent to the depletion of Block 4, underground production will be derived principally from Block 5, a new ore block beneath the current operations, which has probable diamond reserves of 25.3 Mcts at a grade of 58.6 cpht. In order to provide earlier access to undiluted ore in Block 5 before the main block cave is put in place, Petra will use the sub level cave (“SLC”) mining method over four levels in Block 5 from 700 mL to 780 mL and is currently ramping up the underground operation to achieve steady state throughput of 3.5 Mtpa from FY 2018. As at the end of FY 2016, mining is currently transitioning from the block cave on the 630 metre level (“mL”) to an SLC over four levels from 700mL to 780mL.  The new Block 5 cave will then be installed at 900 mL from FY 2023/FY 2024.

As the mine’s production profile gradually changes from diluted to undiluted ore, the ROM grade is expected to increase to 53-55 cpht in FY 2017 and 55-58 cpht from FY 2018 onwards – read more about the impact of moving into undiluted ore.

In addition to underground mining, we are also currently reprocessing the ‘Pre 79 Tailings’ dump at Finsch. Tailings throughput is planned to come to an end after FY 2017 when this dump is depleted. There remains an additional tailings dump at the mine, the ‘Post 79 tailings’, but this is not currently included in our mine plan.


Click on schematic to enlarge.

The orange blocks indicate the Block 5 SLC and the Block 5 Block Cave that are currently in our mine plan to 2030. The blue block indicates the potential future block to be accessed post 2030.

Mining Right

Finsch Diamond Mine (Pty) Ltd (“FDM”) holds a valid new order mining right (the ‘‘Finsch Mining Right’’) dated 15 October 2008. The Finsch Mining Right was initially issued to De Beers under item 7 of Schedule II of the Mineral and Petroleum Resources Development Act, 28 of 2002 (“MPRDA”) and was ceded to FDM by notarial deed of cession on 8 September 2011 and duly notarially executed and registered in the Mineral and Petroleum Titles Registration Office.

The Finsch Mining Right confers on FDM the exclusive right to mine for diamonds in relation to the areas it refers to until 14 October 2038. Pursuant to the MPRDA, the Finsch Mining Right is renewable (for periods of up to 30 years for each renewal) on the basis more fully set out in section 24 of the MPRDA.

Section 2 of the Mineral and Petroleum Resources Royalty Act No. 28 of 2008 (“the Royalty Act”) requires FDM to pay the South African Government a royalty for minerals recovered under the Finsch Mining Right. Pursuant to section 4 of the Royalty Act, the royalty is to be paid on gross sales in accordance with a defined formula set out in the Royalty Act. The formula applicable to rough diamonds is as follows: 0.5% + (earnings before interest and taxes, as defined in Section 5 of the Royalty Act / (gross sales x 9) x 100) but not exceeding 7%.

In addition, South Africa has a rough diamond export levy requirement of 5% as set out in section of the Diamond Export Levy Act 15 of 2007 (“Export Levy Act”). Producers are however exempt from this levy in respect of production that is exported provided that a certain percentage of their production is sold to local diamond beneficiation licence holders, on the basis more fully set out in sections 7, 8 and 9 of the Export Levy Act.

FDM is also subject to corporate tax in South Africa at the rate of 28% in terms of section 5 and other provisions of the Income Tax Act 58 of 1962.

There are no fiscal stabilisation provisions in place in relation to Finsch Diamond Mine.


“Finsch: A world-class operation: Every now and again, you come across a real gem of a mine that isn’t just about the commodity, but rather the entire mine, and the manner in which it is managed and operated. Petra’s Finsch diamond mine is such a mine.” Tony Stone

Read an article on Finsch in Inside Mining, June 2015


  • Sept 2011 Acquisition by Petra
  • 2.21m carats FY 2016 Production
  • 49.1m carats Total diamond resource


finsch Diamonds

Two Finsch diamonds of 36 carat and 43 carat – November 2013