Which of these rocks would be good for:

• Making a statue - all except mudstone and coal (too soft) - it would be difficult to make a statue from some because they are so hard, eg. granite, metaquartzite
• Building a dam - all except mudstone and coal (too soft), conglomerate (too variable), slate (too easily broken in one direction)
• Making a fireplace - anything that is attractive - except mudstone and coal (too soft - and coal would burn)
• Solid foundations - all of them - but the tougher the rock, the better the foundations

Which of the rocks would be best for:

• Storing water within it - sandstone, limestone, conglomerate
• Storing oil or gas within it - sandstone, limestone, conglomerate
• Showing that sedimentary rocks are made of lots of fragments - the fragments are most clear in coarser-grained rocks, conglomerate, sandstone, limestone
• Showing that igneous rocks have interlocking crystals - the crystals are clearest in the coarsest rocks, granite, gabbro and peridotite
• Showing that metamorphic rocks often have aligned minerals - slate, schist, gneiss
• Some rocks contain traces of past life - fossiliferous limestone

Which rocks (2 or more) would best show:

• Sedimentary rocks ranging from coarse to fine - conglomerate to sandstone to mudstone
• The difference between igneous rocks that formed by slow cooling and fast-cooled igneous rocks - coarse rocks (slow cooling - granite, gabbro, peridotite) through medium grained rocks (microgranite) to fine-grained rocks (basalt, andesite, rhyolite)
• Metamorphic rocks that often do not have aligned minerals - marble or quartzite. This is either because the rock was formed by thermal metamorphism, when there was little pressure to cause mineral alignment, or because the minerals don’t easily show alignment - as the calcite in many marbles and the quartz in many metaquartzites.
• The metamorphic rocks that show a sequence of increasing metamorphism from an initial mudstone sedimentary rock - mudstone to slate to schist to gneiss.

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