The Lekkersing quartzite mine is located in the Richtersveld, directly adjacent to the town Lekkersing some 40 km northeast of Port Nolloth, Northern Cape Province. The quartzite has been mined on a small scale since the early 1930’s, but commercial exploitation only commenced in 1965. During the early 1990’s production peaked at some 800m³ quartzite per month run-of-mine from which the on site tile cutting facility produced about 6 000m² tiles per month.Diamond Quartzite Processing is a subsidiary of Elaria Holdings (Pty) Ltd.
GEOLOGICAL SETTING AND LOCATION
The Lekkersing quartzite deposits occur in a quartzite horizon, the Lekkersing Formation, belonging to the Stinkfontein Subgroup of the Gariep Supergroup. The formation consists of two quartzite horizons separated by and overlain of conglomerate units. Sediments of the Stinkfontein Subgroup were deposited during the Pre- Cambrian Namibian era (approximately 900 million years ago) in a shallow marine environment.
The Lekkersing area occupies the upper near horizontal limb of a major regional asymmetric fold verging east. The main fold axis is orientated north-northeast to south-southwest, gently plunging in a south- southwesterly direction. The main axial plane is generally parallel to the upper limb resulting in the bedding planes being very regular, unfolded and therefore always parallel.
The quartzite is made up of well-sorted, medium to coarse silica grains and is slightly porous with a high compressive strength. The high mica content in the micaceous layers allows for easy separation of layers and therefore good recovery of quartzite slabs at depths exceeding 30m below surface.
The dominant structural feature that has significant influence on the mining and recovery of quartzite is the well-developed joints present in the quartzite (Cosi, 1994). Cleavage predominantly follows the layering of primary sedimentary bedding planes dipping 35° to 45° on a bearing of 290° west-northwest. In the weathered zone near the surface, cleavage planes have been accentuated by weathering and are particularly enhanced by the limonitisation along the mica rich layers.
Good exposures of laminated grey quartzite outcrops occur in the excavations of the main quarry. Cross bedding layers are relatively even in thickness and display fairly smooth surfaces. Sterile bands of greywacke approximately 150m wide run north-south across the flat bedded quartzite.
At Lekkersing the best quality quartzite is obtained from the beds that exhibit bedding with a pronounced lamination, the planes of which are from approximately 2.5mm to 80mm apart. Mica rich layers tend to enhance the cleavability of the quartzite and therefore the recovery of good quality cleft stone. The uniqueness of the deposit lies in the nature and quality of the flat-bedded quartzite, traditionally referred to as flagstone.
The Lekkersing quartzite is a whitish, laminated micaceous quartzite which is generally recrystallised, with muscovite mica on the bedding-planes giving the surface an attractive silvery appearance with a vitreous lustre. The quartzite is a metamorphic assemblage of quartz (96-98%), mica (2-3%) and trace amounts of iron, aluminium and titanium.
The quartzite slab exhibits a very uniform thickness and sufficient hardness to allow the production of high quality natural tiles at a very low cost. These factors render the Lekkersing quartzite highly suitable for the manufacture of a range of products by the processing facility on site.
Diamond Quartzite is a durable, beautiful and very unique Natural Stone. In the natural stone market, it is the ideal alternative for any designer, architect, builder or home owner who is seeking an alternative to the common natural stones currently available on the market. Some common applications for quartzite include, but are not limited to, Feature walls, Decorative landscaping, Water Features, Interior and Exterior paving and tiles, Wall cladding, Mosaics and Swimming pool surroundings.
THE MINING RIGHTS
The new order mining right, under reference number (NC) 30/5/1/2/2/506 MR and the Environmental Management Programme Report, were approved and granted in August 2007 on a thirty year term. The new order mining right area granted is identical to the old order right. The resource base is extensive and provides sufficient material for over 60 years. A surface rental agreement with the Richtersveld Community comprising an annual surface rental and a monthly rental for the factory facilities has been negotiated. A royalty of 1% is payable to the State.
The Lekkersing quartzite slabs exhibit a very uniform thickness and sufficient hardness to allow the production of high quality natural tiles at a very low cost. These factors render the Lekkersing quartzite highly suitable for the manufacture of a range of products by the processing facility on site.
Future revenue will not be limited to sales, since the Lekkerstone Mine operates in a niche market and is producing a “finished product” for which new trends in architecture have created a demand.