Context
Recently, a research was conducted on Stonehenge's 52 sandstone megaliths, which is known as sarsens, to gain insight into its geology and chemistry. It revealed some of the traits of building material for the famed monument in southern England to show their stout resistance to weathering.
About the Stonehenge megaliths
- Stonehengeis a prehistoric monument built under the Neolithic and Bronze Age in around 2500 BC.
- This is located in Wiltshire, England.
- This consists of an outer ring of vertical sarsen standing stones,
- The stones are around 13 feet high, seven feet wide, and weighs around 25 tons
- The inside ring is consists of smaller bluestones.
- It also has free–standing trilithons, two bulky vertical sarsens joined by one lintel on the inner side.
- The whole monument is orientated towards the sunrise on the summer solstice.
- The site and its surrounding area were added to UNESCO’s list of World Heritage Sites in
What are the findings of the research?
- The researcher was conducted used CT-scan, X-rays, microscopic analyses, and various geochemical techniques.
- The sarsens are made of stone known as silcrete which forms gradually within a few meters of the ground surface due to the groundwater washing through buried sediment.
- The silcrete is comprised of mainly sand-sized quartz grains which are cemented tightly together by an interlocking mosaic of quartz crystals.
- Quartz is extremely durable and does not easily crumble or erode even when exposed to eons of wind and weather.
This explains that why the stones are resistant to weathering and why they made ideal material for monument-building.
