Mining Intelligence and News
Lesotho

Mothae Mine

Click for more information

Categories

Overview

Mine TypeOpen Pit
StatusActive
Commodities
  • Diamond
Mining Method
  • Truck & Shovel / Loader
Production Start... Lock
Mine Life... Lock
SnapshotThere were significant performance improvements at Mothae following the plant and operational changes made at the beginning of 2023. Modifications made to the plant flow sheet and upgrades to the XRT (X-Ray Transmission) sorter eliminated the previous processing limitations related to hard ore.

Owners

SourceSource
CompanyInterestOwnership
Government of the Kingdom of Lesotho 30 % Indirect
Lephema Executive Transport (Pty) Ltd 70 % Indirect
Mothae Diamonds (Pty) Ltd. (operator) 100 % Direct
14 August 2024, Lucapa Diamond Company Limited announces it has successfully completed the divestment of its 70% stake in Mothae Diamonds (Pty) Ltd, which owns the Mothae Diamond Mine to local Lesotho company Lephema Executive Transport (Pty) Ltd.

The remaining 30% of Mothae Diamonds is held by the Government of Lesotho.

Conducted by Mothae Diamonds Pty Ltd.

Deposit type

  • Kimberlite

Summary:

The Mothae kimberlite intrusion is a kimberlite diatreme, or pipe, which was the feeder to a now eroded kimberlite volcano.

The Mothae kimberlite is situated on the southern edge of the Kaapvaal Craton, which extends through central, eastern and north-eastern South Africa, into southern Zimbabwe and southeastern Botswana, and incorporates most of Swaziland.

As the diamondiferous Northern Lesotho Kimberlite Field is in the Kaapvaal Craton, it conforms to ‘Clifford’s Rule’, which states that diamondiferous kimberlites tend to occur in geological regions that have been tectonically stable since the Archaean.

The Archaean basement in Lesotho is entirely covered by the flat-lying Paleozoic to Mesozoic Karoo Supergroup which reaches a thickness of approximately 4 km in Lesotho.

The surface geology within the Mothae license area comprises amygdaloidal and nonamygdaloidal Mesozoic (180 Ma) Drakensberg Group flood basalt, into which the Mothae kimberlite has intruded. The average elevation of the Mothae kimberlite is approximately 2,900 mamsl and the thickness of the basalt into which it is emplaced is estimated to be of the order of 1,000 m, although basalt thickness on the property may locally reach up to 1,400 m. Basalts are underlain by Beaufort Group sediments of the Karoo Supergroup.

Kimberlite emplacement during the Cretaceous Period was widespread throughout southern Africa and was probably associated with tectonic triggers during the break-up of Gondwana (Bailey, 1992).

The Mothae kimberlite consists of a main southern pipe-like lobe (South Lobe) connected to a smaller northern lobe (North Lobe) by an elongate central kimberlite body (Neck). The South Lobe has a surface expression of 5.05 ha and the three areas combined form a total surface area of 8.81 ha. Wall rock contacts for the North and South Lobes have been delineated by geophysical data, mapping and drill core intercepts. The contact between the kimberlite and the basalt is typically sharp and steep with localised zones of wall rock breccia.

The kimberlite itself comprises almost entirely of massive volcaniclastic kimberlite (“VK”) of different types. The different kimberlite types have been ‘fingerprinted’ in terms of their Kimberlite Indicator Mineral (“KIM”) content and petrographic characteristics as a control on bulk sampling; this being important as each has a different diamond grade and revenue.

Reserves

Lock

- subscription is required.

Mining Methods

Lock

- subscription is required.

Comminution

Crushers and Mills

Lock

- subscription is required.

Processing

Lock

- subscription is required.

Production

2020 was a disjointed year for Mothae as a consequence of the COVID-19 pandemic, with the mining operations being suspended from the end of March 2020 to the beginning of October 2020.
CommodityUnits20232022202120202019
Diamond carats  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe30,107
All production numbers are expressed as mineral.

Operational metrics

Metrics20232022202120202019
Total tonnes mined  ....  Subscribe  ....  Subscribe
Tonnes processed  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe1,156,093 t
Annual processing capacity  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe1.1 Mt

Production Costs

CommodityUnits20222021
Cash costs (sold) Diamond USD  ....  Subscribe
Total cash costs Diamond USD  ....  Subscribe

Operating Costs

Currency20222021
Total operating costs ($/t milled) USD  ....  Subscribe  ....  Subscribe

Financials

Units20232022202120202019
Capital expenditures M USD  ....  Subscribe  ....  Subscribe
Revenue M USD  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe 16.5  
Pre-tax Income M USD  ....  Subscribe  ....  Subscribe
After-tax Income M USD  ....  Subscribe  ....  Subscribe
EBITDA M USD  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe 1.2  
Operating Cash Flow M USD  ....  Subscribe  ....  Subscribe

Heavy Mobile Equipment

Fleet data has not been reported.

Personnel

Mine Management

Job TitleNameProfileRef. Date
....................... Subscription required ....................... Subscription required Subscription required Aug 18, 2024
....................... Subscription required ....................... Subscription required Subscription required Aug 18, 2024
....................... Subscription required ....................... Subscription required Subscription required Aug 18, 2024
....................... Subscription required ....................... Subscription required Subscription required Aug 18, 2024
....................... Subscription required ....................... Subscription required Subscription required Aug 18, 2024

EmployeesContractorsTotal WorkforceYear
...... Subscription required 2022
...... Subscription required ...... Subscription required ...... Subscription required 2021

Aerial view:

Lock

- subscription is required.