Page 6 - Curriculum Visions Dynamic Book

Lead minerals
Lead forms a natural compound with many other elements, but it is most commonly seen as crystals of lead sulphide, where it is known as the mineral galena. It is a very heavy mineral, about three times as dense as most rocks.
Galena forms crystals that are shaped like cubes with a dull grey (lead grey) colour. The crystals are soft for a mineral, about the same hardness
as a fingernail. This is why galena will mark surfaces with a dull grey line.
 Lead ore being mined. Here a drill is being used to make holes for explosives to blast the tunnel face. The tunnel is following the metamorphosed rock that surrounds a fissure.
 The location of hydrothermal deposits in fissures above a magma source.
Layers of sedimentary rocks are pushed up by the rising magma.
Hydrothermal veins in which minerals are concentrated.
Magma from below the Earth’s crust initially heats the surrounding rocks but eventually cools to form granite.
Rocks around the hot magma chamber are metamorphosed or changed.
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