Randeniya Vein Quartz Deposit

Introduction and Origin of Deposit

The chemical composition of quartz is SiO2 and the name vein quartz is used for the quartz deposits in the form of a vein, which had originated due to igneous activities. Quartz with extreme purity over 99 percent of SiO2 is endowed with many parts of Sri Lanka as discordant veins and is confined to the central Highlands, especially towards the Highland/Vijayan lithological boundary.
Wellawaya Veins Quartz Deposit occurs along the Highland/Vijayan boundary. In here, Orientation of veins in an irregular manner, short vein segments with unequal thickness, appear without clearly define sharp contact presence the significant features in the vicinity of Wellawaya.

Occurrence

Based on geological, textural and mineralogical data suggest that quartz veins bear evidence of single stage crystallization. Wellawaya vein quartz occurrence exhibits glassy nature of mineral grains. This reveals that crystal grains don't define regular crystal habits or crystal boundaries due to fast cooling processes of crystallization. Fast cooling of materials might have been caused by the high-temperature disparity of country rock and hot aqueous solution.

Other abundant Minerals in Quartz Deposit

Deposit exhibit different types of quartz minerals. They are Crystal Quartz, Rose Quartz, Smoky Quartz and Milky Quartz. But Milky Quartz is the most abundant Quartz variety in this deposit.
In some places of the Quartz deposit have pure feldspar layers between the Quartz layers. Feldspar contains very less amount of mica.

Ongoing processes in the plant

The first operation process of Randeniya plant is drilling. The drill holes are filled with water gel and AMFOR. Detonators are used as explosives to blast the deposit. Breaker machines used to break down boulder into small particles. Then separated by visual identification into quartz from other impurities. Finally, Good quality quartz has been transported to Digana plant and low grade quartz to ceramic companies. In Digana plant, they have been exported quartz (5 micron size particles) to China, Japan, Korea like countries.

Mining process

Mining has been referenced GSMB survey data. They use detonators and Ammonia powder for blasting. After the blast, it carries out into hand sorting. Quartz particle size reduction done by human labores.

Uses of Quartz

High purity quartz important to produce fused quartz and Silicon, which are used in computer chips and other electronic devices. Other than that there is a demand for high purity silica powders of submicron size in various industries. Grinding of quartz is comparatively difficult because of its high hardness (Moh’s scale hardness is 7). In Sri Lanka, vein quartz is mainly used in the ceramic industry as a major raw material.

References

  • www.gsslweb.org/home/files/17-20%20HEWATHILAKE-final.pdf‎ , Feb 22, 2013 - Deposit in Buttala, Sri Lanka. H.P.T.S. Hewathilake1, J.T. Cooray1 and S.N. De Silva2. deposit (Magnetite deposits), Secondary iron ore.
  • http://www.nation.lk/2007/03/04/busi1.htm Mar 4, 2007 - ... world's best iron ore deposits, the Uva Magnetite Deposit of Buttala.
  • http://www.gsmb.gov.lk/web/index.php?option=com_content&view=article&id=95&Itemid=72&lang=en Mar 19, 2010 - Resistivity surveys at Randeniya vein quartz deposit and Wellawaya and Aruwakkalu limestone deposit.
  • Geology and Mineral Resources of Sri Lanka thakshana.nsf.ac.lk/pdf/VIDURAWA/VIDU_30_1/VIDU_30(1)_7.pdf‎ by S Jayatileke