The Parthenon
Overview
The Parthenon, located in Athens, Greece, is a well-known piece of ancient Greek architecture dedicated to the Ancient Greek God Athena. It was completed in 477 BC and took 9 years to build. The temple was built atop a large hill called the Acropolis, made from predominantly schist and limestone, whereas the Parthenon is made from marble.
Marble
Marble is a limestone which has been metamorphosed due to high degrees of heat (more than 400°C) and pressure. It is mainly made up of calcite, however, it can contain other minerals like quartz, pyrite and mica. It can be seen with a pink hue due to iron oxide being present, however, in the Parthenon, the marble is a pristine and opaque white although when it was built some of it would have been painted a variety of vibrant colours. We know this because tiny traces of colour are present such as Egyptian blue, meaning they were never supposed to be the aforementioned pristine white that most people think of.
I have found a sample of some marble to conduct tests on, which could potentially explain why the Greeks used marble to design the Parthenon. The results from the test have been recorded in the table below. To conclude the results, the sample of marble I tested had a hardness between 2.5 and 3.5 because it was scratched by a copper coin but not by my fingernail, and it effervesced with acid proving that it contains calcite. This would suggest that it has good erosion properties however it is not very chemically resistant which could be an issue.
However according to research, the marbles were used because it was readily available in local quarries, and because they were visually remarkable to look at, representing the God Athena's beauty in their flawless nature. In addition, the temple needed to last for generations to come and so the material used to build it had to be resistant to erosion like attrition and abrasion, and weathering. This means it had to have a high hardness which marble certainly has as concluded by my tests, but perhaps the biggest evidence for this is that the Parthenon is still around today almost 2500 years after it was built.
The Geology of the Acropolis
The top of the Acropolis is made from Tourkovounia Limestone and sits atop Athens Schist. This is peculiar because the Limestone is older than the Schist, so using the superposition principle, the Schist should be above the limestone, as it is the younger rock by nearly 30 ma. It is assumed that this occurred due to a thrust fault causing the limestone to slide onto the schist.