Precious Metal Clay
is a patented material developed by Mitsubishi Materials Corporation of
Japan in 1993. The principle ingredient in PMC is tiny metal particles
only 20 microns in diameter. As a point of reference, it would
take as many as 25 of these particles to make a single grain of table
salt. The remainder of the material consists of water and an organic
binder. After firing, both the water and binder have been completely
removed, so PMC may be hallmarked and will assay as .999 pure.
Three years
after introducing PMC, Mitsubishi Materials Corporation developed a
second version, called PMC+
. Marking a historical point in the process of
precious metal production, PMC+ cut the firing time and working
temperature of such materials significantly.
Then in 2002 Mitsubishi Materials
Corporation developed yet another version of silver clay, called
PMC3.
By incorporating
even smaller particles of silver into the clay like
medium, this third generation of PMC fires even cooler than PMC+. PMC3
fires faster and has a higher tensile strength than either of the
previous silver clays.
PMC may be hallmarked and will assay as .999 pure.
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PMC
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PMC+
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PMC3
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Workability
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Excellent
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Slightly Stiff
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Excellent
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Strength
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pretty good
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very good
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very good
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Recommendations
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pendants
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rings
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rings
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brooches
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pendants
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charms
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charms
beads |
bracelets
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pendants
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All three kinds
of clay are worked with the same
tools,
fired in the same
kiln, and can be finished in
exactly the same way. However, PMC+
and PMC3
fires in a much shorter amount of time and shrinks less!
PMC products can be worked with in much the same manner as
modeling clays. Many techniques can be incorporated ranging from
hand forming, coiling, throwing on a wheel, and sculpting with
simple tools.
The PMC slip
can be painted on or
dipped. The
syringe
can be used to make
fine detailed pieces, or add detail to a piece formed from the
clay PMC.
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Firing Schedules for PMC products
*Indicated weight
shows the silver content per package.
Silver PMC (original)
can be fired for
2 hours at 1650°F - 900°C
Shrinkage 25-30%
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Silver PMC+
can be fired using one of three schedules:
10 minutes at 1650°F - 900°C
20 minutes at 1560°F - 850°C
30 minutes at 1470°F - 800°C
Shrinkage only 10-15%
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Silver PMC3
can be fired using one of three schedules:
10 minutes at 1290°F - 700°C
20 minutes at 1200°F - 650°C
30 minutes at 1110°F - 600°C
Shrinkage only 10-15%
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Melting Point For Fine Silver 1752°F
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Gold PMC 24k
can be fired for
for 2 Hours at 1830°F - 1000°C
Shrinkage 25-30%.
All Precious Metal Clay
Products Must Be Fired. |
Finishing is almost as versatile as the
forming process. A soft
brass brush
is one of the best ways to begin burnishing your new creation, followed
by a polishing compound and even metal polishing tools. Silver PMC
can be colored with
liver of sulfur
an excellent
oxidizer, or colorants
and soldered as with conventional metals.
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