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Manufactured
Diamond - a Dream of Mankind
And a Long Series of Unsuccessful Attempts
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James
Hannay
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Henri
Moisson
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Sir
Charles A. Parsons
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| Dr.
Percy Bridgman |
Mankind has been dazzled by the mysteries of the gleaming
diamond since it was first discovered centuries ago
among alluvial deposits in the riverbeds of India. The
glistening, bright, rare material, formed deep beneath
the earth’s surface, was treasured first for its
beauty as a dazzling gemstone. Later for its physical
characteristics of hardness, thermal conductivity, low
coefficient of friction, light refraction properties,
resistance to chemical attack and permanence over time.
In the 1860s, diamond was discovered in South Africa,
where it had surfaced through the earth’s mantel
by volcanic action. They have since been discovered
in other countries, including South America, Russia
and Australia.
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| Antoine-Laurent
Lavoisier |
Efforts to synthesize diamond date back several hundred
years. As early as 1770 Antoine-Laurent Lavoisier, a
French scientist, was credited with proving diamond
is a crystalline form of carbon, the basic element found
in all living matter. Scientists would later discover
carbon atoms in graphite are arranged in two-dimensional
hexagonal planes stacked one above the other, with each
atom attaching to three others in the plane, making
the substance slippery to the touch. In diamond, however,
the atoms of carbon are packed in three dimensions,
with each carbon attaching to four others, forming the
hardest material known.
Scientists theorized that if the atomic composition
of carbonaceous materials was manipulated, diamond could
be made in the laboratory. While it was generally believed
this change was caused by high temperatures and high
pressures, the exact process was a mystery that fascinated
many scientists during the 1800s and early 1900s.
Some believed they had created diamond in the laboratory,
only to discover later their experiments could not be
replicated. In 1880, James Hannay of Scotland thought
he made diamond when he heated a mixture of hydro-carbons,
bone, oil, and lithium to red heat in sealed iron tubes.
Twelve years later, French scientist Henri Moisson thought
he had made a diamond when he superheated carbon and
metals to white heat in a special electric-arc furnace,
then plunged them into water or molten lead. Claims
by these scientists were later dashed by an Irishman,
Sir Charles Algernon Parsons, who studied their experiments,
as well as conducted his own. He concluded no one had
ever created a synthetic diamond.
In the 1940s Nobel Prize physicist Dr. Percy Bridgman
of Harvard University, began a series of experiments
supported by an industrial group. Bridgman designed
equipment capable of recreating the high pressures and
the high temperatures found deep within the earth. While
he was successful in heating graphite to 3000°C
(5432°F) under pressures of 600,000 psi (4137 MPa)
– greatly adding to the understanding of carbon
under these conditions – he was also unable to
produce diamond. The experiments were abandoned within
three years.
Growing Strategic Value of Industrial Diamond
The search for a synthetic diamond resumed in the late
1940s to meet a growing national need. During the Cold
War Era, the U.S. industrial force had slowly become
dependent on natural diamonds. Diamonds were needed
to sharpen cemented tungsten carbide tools used in metalworking,
for sawing or drilling stone and concrete, as well as
for dressing tools used for grinding wheels and for
polishing applications. The only source for these diamonds
was overseas. Clearly, a stable, dependable source of
diamond was needed.
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