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Enameling can be a tedious media, requiring
painstaking attention to surface preparation and firing times. The
average time a piece is in the kiln is 40-60 seconds, with only
an 8 second leeway between the enamel being fired to maturity, and
the underlying metal beginning to break down and melt. Firing time
is critical as the melting point of silver is 1640 degrees, and
the enamel fuses at 1550 degrees.
 The
transparent enamels I work with are imported from Austria, Japan
and France. These glass enamels are specifically designed to tolerate
the rapid changes in temperature that occur when a piece is fired,
and is brought from 70 degrees to 1600 degrees in a matter of seconds.
The enamels fuse to the metal in a similar way that a glaze fused
to a pot.
The
technique that I specialize in is Champlévé. This
is a French term, though the technique dates back as far as the
Byzantine Enamels of the 12th century and before. In this technique,
recessed areas are created for the enamel, either by construction,
casting, etching, or engraving. In my work I utilize the two former
techniques.
I
begin by transferring my design to a sheet of 22g Sterling silver.
Areas to be enameled are pierced out of the interior of the sheet
of Silver. This cut out sheet is then sweat soldered to a backing
sheet, also of Sterling Silver. The outside edges of the piece are
cut to the specifications of the design, accent pieces of 18k gold
are soldered into place, and the piece is heated and quenched in
acid several times to raise a layer of Fine Silver to the surface.
(Fine Silver is too soft to work with, and Sterling Silver has the
hardness that I need, but is alloyed with nickel etc, which does
not bond well with enamel.)
The
enamel is ground to the consistency of fine sand, washed and mixed
with water. A thin layer of enamel called Flux is applied first
using a tiny watercolor brush. I often put down a layer of pure
24k Gold and/or Fine Silver foil over the Flux. The light that is
reflected off the crinkled surfaces of the foil shining from behind
the enamel will help to create the effect of mysterious and luminous
muted windows of color. As many
as thirty firings of colored transparent enamel may be required
for the recessed areas to be overfilled sightly. The piece is then
ground down flat with the surface of the metal.
At
this point the piece is refired to heal the scratches created by
the grinding process and the enamel emerges from the kiln with a
smooth and glossy surface. The final soldering, such as pin backings
or earring posts is done at this time. In my work I prefer a matte
finish on the enamel, and achieve this either by immersion in an
acid solution, or in the case of the one of a kind pieces, with
hand-sanding.
Finally,
the Silver is oxidized to a steely gray color by dipping it into
a malodorous solution of Liver of Sulfur. I then rub the surface
with pumice or steel wool to burnish it to a soft glow.
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