Mineral Resources Potential - Geothermal Resources

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I
MetallicMinerals 115
I But more than half of the Iead used currently comes from recycling
I (Hutchison, 1983).
Applications
Lead is a major constituent of the Lead-acid battery used
extensively in car batteries. Lead was used as a white pigment in
Lead paint. It is used as a colouring element in ceramic glazes,
notably in the colours red and yellow. Lead sticks were used as
pencils, but has been replaced by graphite for the last 450 years.
The element is used as projectiles for firearms and fishii sinkers
because of its density, low cost verse alternative products and ease
of use due to relatively low melting point. Lead is used in same
candles to treat the wick to enswe a longer, more even burn. Lead
is used as shielding from radiation. Molten lead is used as a
coolant, e.g. for lead-cooled fast reactors. Lead glass is comprised
of 12-2Ph lead. It changes the optical characteristics of the gIass
' and reduces the transmission of radiation. Tetraethyl lead has been
used in leaded fuels to reduce engine knocking; however, this is no
longer common practice in the Western World due to health
concerns. Lead is used as electrodes in the process of electrolysis
(Gilbert and Parks, 1986).
Origin
Lead-zinc deposits are generally accompanied by silver, hosted
within the lead sulfide galena or within the zinc sulfi& sphalerite.
LRad and zinc-deposits are formed by discharge of deep
sedimentary brine onto the sea floor (termed sedimentary
exhalative or SEDEX), or by replacement of limestone, in skarn
deposits, some associated with submarine volcanoes (called ,
volcanic-hosted massive sulfide or VHMS) or in the aureole of
subvolcanic intrusions of granite. The vast majority of lead and