The Politics of Building Stone: Seattle

Twenty years ago today a building stone brouhaha erupted in Seattle.  On that snowy Friday, local newspapers reported that Metro, which managed King County’s sewage treatment and public transportation, would have to pay for, but not use, a half million dollars worth of granite that it had purchased for a new bus tunnel through downtown Seattle.  The reason for the rejection was that King County (Seattle is the county seat) had a policy that it could not use or purchase any goods “manufactured or fabricated” in South Africa because of apartheid.

The conflagration began when Eddie Rye of the Black Contractors Coalition notified Metro about its planned use of a green granite quarried in South Africa.  At the time, the stone, known in the trade as Verde Fontaine, sat in Italy, where it had been shipped for cutting and polishing.  Metro Council executive Alan Gibbs responded that using the stone would be “an affront to the community.”  Officials added that Rye’s notification was the first time Metro had heard of the granite’s origin and that none of the South African had been shipped to Seattle.  Turns out that neither statement was true and that a second South African granite had also been purchased. 

 Travertine and Verde Fontaine

Quarried near Bitterfontein, about 200 miles north of Cape Town, the pine green Verde Fontaine solidified underground over one billion years ago.  The green coloration comes from the mineral chlorite, which forms from the alteration of iron- and magnesium-rich minerals within the rock.  The granite is part of a suite known as Spektakel and were emplaced into supracrustal rock units (metasedimentary and metavolcanic rocks) that most likely exceed two billion years in age. 

After Rye blew the whistle, officials within Metro described how some had known about the origin of the stone but that they thought that so little was to be used that it wouldn’t be a problem.  They also noted that use of the rock technically wasn’t illegal because it was only quarried in South Africa but cut and finished in Italy. King County Council Chairman Ron Sims, a member of the Metro Council, responded ”It was a morally repugnant decision. Somebody should have to account for that. This was no longer a half-million-dollar ‘error.’ It was a conscious decision to defy public sentiment.” 

Accusations continued over the next month ultimately leading to the resignation of Alan Gibbs in late February. ”The buck stops with me,” Gibbs said at a news conference where he read a formal letter of resignation. ”The events of the last few weeks surrounding the issue of South African granite have been an embarrassment to the agency … This episode needs to be put to rest so the agency can move ahead with the important work before us.”  Two weeks after Gibbs’ resignation, an internal review of Metro concluded that Gibbs had not misled the public.  On September 15, 1990, the bus tunnels under Seattle opened, with walls covered in less polemical rock.

Building Stones of Great Edifices: Stonehenge

This will be the first of what I hope to be periodic postings about the building stones of famous edifices, such as the Great Pyramids, Machu Pichu, and the Great Wall of China.  Suggestions would be welcome. 

Some of the world’s oldest building stones made it into a fine story in this month’s issue of Earth.  Written by English geologist Brian S. Johns and Lionel E. Jackson, Jr., a Quaternary geologist from British Columbia, the article offers a thought provoking and believable account of the travels of the enigmatic rocks used at Stonehenge.  In doing so, they answer one of the great questions posed by anyone who has visited the Salisbury Plain, “How the hell did they do it?” 

From wikipedia

As Johns and Jackson note, this question has led to some dubious answers.  The Celts, Vikings, Phoenicians, Druids, and Romans have all had their day in the spotlight, though the building of Stonehenge, around 4,500 years ago, predates each of these peoples.  Nor were space aliens involved, though that would be a very handy way to explain the many mysteries.  Johns and Jackson don’t provide an answer to who but instead focus on the origin of the stones.  

Two primary types of building stone make up the majority of the monoliths.  The outer ring consists of a 60-million-year old rock known as sarsen sandstone.  (Sarsen is a regional term applied to the boulders found scattered across south central England.)  About 50 sarsen stones occur, either as vertical slabs or horizontal lintels, and comprise Stonehenge’s most famous features, the Pi-shaped trilithons.  The largest sarsens weigh an estimated 40 tons, or about equal in weight to 48 Smartcars.  

The smaller and less abundant bluestones raise more questions.  Made primarily of diabase, but also rhyolite and additional volcanic material, the stones’s origin has been traced to the Preseli Hills of western Wales, more than 125 miles to the west.  At least eight different rock types associated with Stonehenge have been found across seven miles of hills in this region of Wales.  Early researcher Herbert Thomas, who promoted the “human transport” theory for the origin of the bluestones, hypothesized that Stonehenge’s builders sought out these stones because of their magical and medicinal properties. 

Source area for bluestones: From Brian Johns’ web site

Johns and Jackson favor a glacial transport model for the bluestones.  They describe how converging ice sheets from Ireland and Wales funneled erratics from Wales in a “trail leading straight to Stonehenge.”  As evidence of such a conveyor belt-like feat, they report on glaciers in Canada, which ferried erratics in a narrow band over 350 miles south.  In England, this phenomenon provided Neolithic Britons with a ready source of stone for their great structure, no matter why they built it.  And that is the great mystery that not even geology can solve.