The world is full of urban legends: computer viruses that don’t really
exist, thieves who steal human organs, dish soap as pesticide, weird ingredients
in fast-food hamburgers.
Here’s another one: The very top of the Washington Monument is made of
aluminum because it was more valuable than gold, silver or platinum, and because
of this value, it was chosen to be the cap of the monument to honor America’s
first president. True or false?
False.
The Washington Monument is capped with an aluminum pyramid, but for very different
reasons than its value. Since the monument was completed in 1884, the story
about the aluminum pyramid’s expense as a way to honor the country’s
first president has been reinforced in many publications, ranging from Civil
Engineering Magazine to the Washington Post.
Aluminum was indeed rare and costly to produce in the 1880s, when the Washington
Monument was completed, but it was not selected because of its cost, and it
was not even the most valuable metal around. At a cost of about $1 per ounce
then, aluminum cost approximately the same as silver.
“Call me Al”
Aluminum was not the original choice for the pyramid to top the monument. The
purpose of the cap was to serve as a lightening rod. The selection of aluminum
evolved during negotiations between the engineer in charge of the construction,
Colonel Thomas Lincoln Casey (U.S. Army Corps of Engineers), and William Frishmuth,
who was the only aluminum producer in the United States at the time. The preferred
materials for the cap were copper, bronze or brass plated with platinum.
Frishmuth suggested instead that the pyramid should be made of aluminum, which
he estimated would cost $75. Casey accepted the proposal, with a warning to
keep within the estimated cost.
Frishmuth was successful in casting a cap that he pronounced to be a “perfect
pyramide of pure aluminum made of South Carolina Corundum,” which is an
aluminum silicate mineral. The pyramid was 9 inches high and weighed 100 ounces;
it was the largest piece of cast aluminum that had ever been created at that
time. Frishmuth was so pleased with the result that he asked for permission
to exhibit the aluminum pyramid for two days before he delivered it to Washington,
D.C. It was displayed “like a jewel” in the window of Tiffany’s
in New York — undoubtedly adding to the myth of the value of this new metal,
aluminum.
Casey’s response, on delivery of the pyramid, was “the point is received
and is acceptable in every way.”
Then he got the bill.
As it turned out, the estimated cost was exceeded — by a lot. The original
estimate of $75 had turned into an invoice for $256.10. Casey immediately dispatched
his assistant to investigate.
The details about the cost overrun are not altogether clear, although part of
the reason was that the typical sand mold would not work for the pyramid’s
casting, and an iron mold had to be constructed. Another factor may have been
that the cost of the aluminum alone, at the prevailing price, was more than
the estimate. The payment was ultimately $225 — three times the original
estimate.
The capstone and aluminum pyramid were placed on top of the Washington Monument
on Dec. 6, 1884, and the formal dedication was held on Feb. 21, 1885, more than
30 years after construction began. The national media covered both events, and
the aluminum tip was featured prominently. The American pubic, most of whom
had probably never heard of aluminum before, learned in the press that it was
a rare and valuable metal.
Measuring value
The Washington Monument urban legend does make a valuable point, however. The
cost — and therefore the perceived value — of metals depends on several
factors, including the technology available to extract them, the demand for
the product and public perception.
At the time that the metal pyramid capping the Washington Monument was created,
aluminum was very difficult to extract. Although it is the most abundant metal
in Earth’s crust, it occurs in nature only in tightly bonded compounds.
A Danish chemist, Hans Christian Oersted, first isolated small amounts of the
pure metal in 1825. German and French chemists invented new extraction methods
over the next decades, and the price of aluminum dropped from $1,200 per kilogram
in 1852 to about $40 per kilogram in 1859.
Thirty years later, in 1889, Charles Martin Hall, a recent chemistry graduate
from Oberlin College, patented a new method to produce aluminum. His approach
used an electric current passed through a nonmetallic conductor to separate
the highly conductive aluminum. Hall founded the Pittsburgh Reduction Company,
which became the Aluminum Company of America — Alcoa — and which remains
the leading producer of aluminum in the world today.
Overnight, aluminum ceased to be considered a precious metal. By the time Hall
died in 1914, aluminum cost 18 cents a pound (about 40 cents per kilogram).
At that cost, the total value of the aluminum in the Washington Monument’s
cap would have been $1.62 (in 1914 dollars) — rather than the nearly $100
value at the time the pyramid was cast.
For a contemporary comparison, investment analysts in February 2005 expressed
concern that aluminum prices were approaching “record highs” of nearly
$2,000 per metric ton, almost $2 per kilogram. At this rate, the aluminum in
the cap for the Washington Monument would cost about $5.67 in current dollars.
It just goes to show that you don’t need the most expensive material available
to make a great memorial in honor of a great person.
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