SoylentNews

Arthur T Knackerbracket has found the following story:

Excavations at two quarries in Wales, known to be the source of the Stonehenge 'bluestones', provide new evidence of megalith quarrying 5,000 years ago, according to a new UCL-led study.

Geologists have long known that 42 of Stonehenge's smaller stones, known as 'bluestones', came from the Preseli hills in Pembrokeshire, west Wales. Now a new study published in Antiquity pinpoints the exact locations of two of these quarries and reveals when and how the stones were quarried.

[...] The largest quarry was found almost 180 miles away from Stonehenge on the outcrop of Carn Goedog, on the north slope of the Preseli hills. "This was the dominant source of Stonehenge's spotted dolerite, so-called because it has white spots in the igneous blue rock. At least five of Stonehenge's bluestones, and probably more, came from Carn Goedog," said geologist Dr Richard Bevins (National Museum of Wales).

[...] According to the new study, the bluestone outcrops are formed of natural, vertical pillars. These could be eased off the rock face by opening up the vertical joints between each pillar. Unlike stone quarries in ancient Egypt, where obelisks were carved out of the solid rock, the Welsh quarries were easier to exploit. Neolithic quarry workers needed only to insert wedges into the ready-made joints between pillars, then lower each pillar to the foot of the outcrop. [...] The new discoveries also cast doubt on a popular theory that the bluestones were transported by sea to Stonehenge.

Megalith quarries for Stonehenge's bluestones (open, DOI: 10.15184/aqy.2018.111) (DX)

-- submitted from IRC

Original Submission