Overview

Mine Type	Underground
Status	Inactive / Suspended
Commodities	Diamond
Mining Method	Longhole open stoping
Mine Life	...
Snapshot	As of July 2021, the Lace underground mine was flooded and is unlikely to be reopened or redeveloped.

Deposit type

• Kimberlite

Summary:

The Lace Mine lies within the south central Archean Kaapvaal Craton within a subcluster of kimberlites referred to as the Kroonstad Group II Kimberlite Cluster (Howarth, 2010) of which only Lace and nearby Voorspoed have seen formal mining. Four other small kimberlite blows and several dykes are known within the cluster.

The Lace Mine lies within the south central Archean Kaapvaal Craton within a subcluster of kimberlites referred to as the Kroonstad Group II Kimberlite Cluster (Howarth, 2010) of which only Lace and nearby Voorspoed have seen formal mining. Four other small kimberlite blows and several dykes are known within the cluster.

Drilling from surface through the wallrocks into the kimberlites in 1997-98 outlined a relatively simple stratigraphy of Karoo shales to ~60m, Ventersdorp volcanics to ~300m, an intercalated shale/volcanic sequence to ~350m, clean lavas again to 380m, and then Kameeldoorns Formation shales again to ~550m, the deepest wall rock drilling to date, in hole Crown-1. We therefore do not believe that Transvaal Supergroup rocks are present at Lace based on drilling to date.

The Lace kimberlites have been dated at 133.2 +/- 2.8 Ma by the 40Ar/39Ar technique on ground mass phologopite grains, similar to the early Cretaceous ages of the other Kroonstad kimberlites and to other Group II kimberlites in South Africa including Finsch.

Mining Methods

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Comminution

Crushers and Mills

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Processing

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Production

Personnel

Job Title	Name	Profile	Ref. Date
.......................	.......................		Sep 23, 2024