The Man Who Harnessed Tension

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Picture
By Ettagale Blauer
T
here are innovators in every
field, people who push the
envelope and strike out on
new paths, taking their industries
in totally new directions. Steven
Kretchmer is to the world of
diamond setting what Gutenberg was
to the printed word. His research and
experimentation freed the diamond
from the confines of prongs, beads
and channels. He did it with some
unlikely help and worked for some
surprising people along the way.
Today, his restless mind forges ahead
into new areas of metalsmithing, built
on equal parts of amazing vision and
solid technical know-how.
Kretchmer is known for perfecting
the tension setting, a method of
holding a diamond within the embrace
of specially alloyed and treated metal.
It’s a genuine tour de force, and could
easily be called invisible setting were
that term not already in use for quite
a different technique. The diamond
appears to be suspended in midair,
with no visible means of support.
It is, in fact, held most securely
within the entire ring shank, and
R
NE
A
Diamond Jewelry
the
mad
scientist,
pots boiling in his basement.
not simply by the
ends of the shank
as is commonly
believed.
Ironically, though
the diamond is
being held with far more strength
and power than any other method
provides—magnitudes more than
the platinum prongs that grip most
engagement ring diamonds—the
fact that you can see so much of the
stone can give the potential buyer
pause. But, if it’s a genuine tension
setting, and not a tension look-alike,
the diamond is absolutely secure,
so much so that Kretchmer offers a
lifetime guarantee on every one of his
tension-set jewels.
You’re close to the real image
of inventor Steven Kretchmer.
A
lthough Kretchmer has a
Master’s of Fine Arts degree, he is
self-taught in metallurgy. He began,
truly, working in his basement. He
conducted his experiments largely
for the sheer joy of discovering what
he could do with metals.
In the mid- 1980s, he was living
in Santa Fe, experimenting with
64 NEW YORK DIAMONDS NOVEMBER 2004
mokumé gané, a Japanese technique
in which different colored metals are
merged through a lamination process
to take on a wood grain appearance.
His work in that field gained him first
place in the Santa Fe Festival of the
Arts in 1984.
He was also working on blue
gold, an alloy that was more rumor
than fact. But Kretchmer was really
doing it and his experiments came
to attention of the development
department of Harry Winston. “They
asked for certain pieces to test me. I
did a blue gold 300-carat reticulated
necklace,” he recalls.
That did the trick and he was hired as
head of research of precious and exotics
metals for Harry Winston in 1985.
Ironically, Kretchmer says, “I always
like mystical things and the power of
jewelry rather than the prestige that
most people wanted from it.”
K
WhenKretchmer
says he reported to
Ronald Winston, who
had taken over the firm after the
death of his father, it made perfect
sense. Ronald Winston is himself a
scientist whose conversation often
strays to the most technical aspects
of the jewelry world. “Winston was
fascinated by these exotic discoveries
that were unfolding in my lab. A lot
of my stuff comes out of visions of
the future,” Kretchmer says.
Kretchmer moved to the East Coast
to be closer to Winston, and did
his experiments in the basement of
his home in Connecticut. “I would
take the train in every two weeks
to show him my developments,” he
remembers. “They did blue gold at
the time. They didn’t know what
to do with the purple gold the fuzzy
alloys and spring alloys.”
That glorious period lasted for a little
more than a year. The appearance of
a new director put an end to anything
that was not traditional Harry
Winston. Kretchmer says, “Ron called
me personally to break the news. But I
felt very grateful for the time I had for
pure research and I started applying it
to design.”
Having relocated, and with a new
wife and 10-year old stepdaughter,
Kretchmer had to remake his
career. “I went from store to store
presenting my portfolio and taking
commissions,” he says. His wife,
Alma, took phone orders and a
business was born.
retchmer followed his bent
and became a consultant in
exotic metals for Stern Leach. “I
was asked by Hans Appenzeller to
create precious metals that would do
what a steel bracelet did for a design
he was then inventing. It required
incredible elasticity,” he says, adding,
“Elasticity is the left side of the curve
of plasticity.”
Upon questioning by this layperson,
he explained that elasticity can be
moved or flexed and always returns
to its original form. Plasticity on the
other hand is also movable but it
will deform if stretched too far. The
problem, clearly, is to preserve the
ability of the metal to return to the
original form.
Kretchmer drew on work he had
done in the past, citing various
mentors including physicists who
have worked with the military. He
was challenged to make the metal
springy and began delving into alloys
of precious metals. There were many
misses, metals that cracked, that were
not malleable or flexible, the very
antithesis of gold. “The old world
goldsmiths loved gold because
it is malleable,” he says. But
as characteristic of a setting
material, malleability is at the
same time a drawback, and
is the reason that many gold
engagement rings feature
platinum prongs.
Then, he says, there
are materials that are
the wrong color,
that oxidize and
fracture. He calls
them “miserable
alloys.”
“I
started
playing with
these miserable
alloys
and
m a k i n g
them reliably
immalleable,”
he
states,
“that is, to be
66 NEW YORK DIAMONDS NOVEMBER 2004
able to form an object and make
it immalleable.” In other words,
stable.
“I evolved a whole set of alloys that
were heat treated. With steel, you can
heat it and quench it. You heat treat
steel to make it hard. Precious metals
require metallurgical means to make
them springy” he explains.
Ironically, he says, he never
succeeded for that client although
he came close. In spite of that, he
could see that someday, something
useful and perhaps revolutionary
would come out of all that tinkering.
In spite of his “mad scientist, head in
the cloud persona,” he took the very
down to earth step of getting in touch
with patent attorneys. “If I am going
to develop something,” he says, “I am
going to protect it. The legal issues
were clear to me. I had somebody do
a search for precedents.”
N
ot surprisingly the name of
Niessing came up. The German
jewelry firm was known for its
innovative work in precious metals.
Kretchmer says, “It was clear that
the technique he was working
on had never been applied to
gemstone mounting.”
German designer Friedrich Becker,
working for the firm that had been
founded in the 19th century, had
developed a tension setting technique
in the 1960s It was based on a method
In 1992, he presented a line of
tension-set jewelry at the “New
Designer” booth of the JA show.
Since then, he says, “The phone
hasn’t stopped ringing.”
But Kretchmer just used that
moment as the springboard to
further innovation and refinement
of his ideas. “We have perfected the
technology over the years, working to
achieve perfect composition, perfect
homogeneity of the alloy and the exact
engineering specifications,” he says.
Because he protects his
own ideas so vigorously,
he also honors the work
of Niessing, which came
before. Sitting down in a
coffee shop in New York
with the current owner
of Niessing, he says, “We
made an agreement that if
anything we did infringed
on the other, either there
would be royalties or we
would eliminate it from
the line.”
I
Steven’s studio in Upstate New York
of hardening the metal by working it,
physically. But Kretchmer found the
work-hardening technique limiting in
its design applications.
His approach was to change the
very nature of the metal, to create
the hardening within the alloy itself.
In 1992 his years of work earned
him two patents for his method for
manufacturing metal compression
in spring gemstone mountings. One
patent covered rings and the other
was for jewelry in general.
He describes the “eureka moment in
1989 when I took the ring, flexed it
open and it returned like a spring.” To
test his invention, he says, “I mounted
a diamond and threw it against a
concrete wall and it stayed in place.”
n spite of the magical
technical innovation
of the tension-set ring,
one drawback is obvious:
the ring cannot be sized.
Once a client chooses a
diamond, the retailer sends the stone
to Kretchmer where one of his trained
workmen sets it into the ring. Indeed,
to be a true tension-set ring, it must be
made by Kretchmer’s company.
The patent prevents anyone else
from using his exact alloy although, he
says, “People have analyzed the alloy.”
To get around his patent, his
competitors use other techniques that
are, he says, by their very nature not
as secure.
“Those other rings are not heat
treated properly and those diamonds
are in peril. Homogeneity [of
the metal] is essential,” he says.
“Everything is evenly and equally
dispersed throughout the metal. All
of my rings have it; it’s all a spring.”
68 NEW YORK DIAMONDS NOVEMBER 2004
That is, the entire ring is holding the
diamond even though it appears that
the diamond is being held just by the
ends of the shank.
“There is not a thicker area or a
thinner are of the ring from three
o’clock to nine o’clock [or the upper
half of the ring shank]. The spring
power is evenly distributed. By
definition, the whole ring holds the
stone securely,” he explains.
To solve the sizing problem,
Kretchmer has now leapt into another
area of metallurgy, inventing a new
trademarked metal called Polarium®.
This platinum alloy is truly magical
for it has components of magnetism.
Kretchmer says, “A layer of
Polarium® inside the ring shank will
conform to…the wearer’s finger.”
He began working on the alloy 12
years ago and its use in tension-set
rings is still a year or two in the future,
but for Kretchmer, it’s as good as
done right now. In his visionary’s eye,
a magnetic alloy is a logical outgrowth
of his pursuit of heat treatment and
the structure of alloys. “Magnetism
has mystical properties. Nobody can
explain magnetism,” he says.
Because Polarium® has a force field,
he can envision women wearing a
necklace of diamonds that will “follow
the wearer like butterflies. Of course,”
he adds with amusement, “She’ll need
a bodyguard.”
More practically, he says, “The
material and technique are suitable
for clasps because the clasps will lock
automatically.” Patents are pending
on this new invention which is
virtually impervious to scratching.
Kretchmer has already developed a
line of Polarium® rings whose two
halves “click” together, thanks to the
magnetic attraction. The material
is a 777/1000 platinum alloy that
takes advantage of the property
of polarization. It is used in his
Metropolis earrings whose disks seem
to levitate as the wearer moves. It’s
sheer poetry in motion. ◆