Stone has been used for a variety of purposes including using its natural beauty in pieces of art, or in this case, a memorial. So the question is, aside from having artistic merit, can public art provide geology lessons?
The posted coordinates will take you to The Australian Ex-Prisioners of War Memorial. The Australian Ex-Prisoners of War Memorial was opened on the 6th February 2004 to recognise and remember over 36,000 Australians who became Prisoners of War during the Wars of the 20th Century. The memorial symbolises that all Australian prisoners embarked on a journey to serve away from their homeland and acknowledges the hardship, deprivation, brutality, starvation and disease endured by Prisoners of War during their capture and the scars that many continued to endure upon their repatriation to Australia. In these magnificent Botanical Gardens the Memorial is a place of quiet reflection and a place to remember loved ones and to mourn those 8,600 Prisoners of War that died in captivity and remain buried on foreign shores.
Some geology: There are two types of stone found at the memorial: Granite and Basalt.
Granite: Granite is a common type of felsic intrusive igneous rock that is granular and phaneritic in texture. The word "granite" comes from the Latin granum, a grain, in reference to the coarse-grained structure of such a holocrystalline rock. The term 'granite' also applies to a group of intrusive igneous rocks with similar textures and slight variations on composition and origin. These rocks mainly consist of feldspar, quartz, mica, and amphibole minerals, which form interlocking, somewhat equigranular matrix of feldspar and quartz with scattered darker biotite mica and amphibole (often hornblende) peppering the lighter color minerals. Occasionally some individual crystals (phenocrysts) are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic texture is known as a granite porphyry. Granites can be predominantly white, pink, or gray in color, depending on their mineralogy. By definition, granite is an igneous rock with at least 20% quartz and up to 65% alkali feldspar by volume.
Basalt: By definition, basalt is an aphanitic igneous rock with less than 20% quartz and less than 10% feldspathoid by volume, and where at least 65% of the feldspar is in the form of plagioclase. Basalt features a glassy matrix interspersed with minerals. The average density is 3.0 gm/cm3. Basalt is defined by its mineral content and texture, and physical descriptions without mineralogical context may be unreliable in some circumstances. Basalt is usually grey to black in colour, but rapidly weathers to brown or rust-red due to oxidation of its mafic (iron-rich) minerals into rust. Although usually characterized as "dark", basaltic rocks exhibit a wide range of shading due to regional geochemical processes. Due to weathering or high concentrations of plagioclase, some basalts are quite light coloured, superficially resembling rhyolite to untrained eyes. Basalt has a fine-grained mineral texture due to the molten rock cooling too quickly for large mineral crystals to grow, although it is often porphyritic, containing the larger crystals formed prior to the extrusion that brought the lava to the surface, embedded in a finer-grained matrix.
Your task:
Find the "wreath laying stone". What sort of stone is it? How does the top of the stone differ to the back of the stone? Describe the differences in colours and texture.
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