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A Tulip Brooch
Our historical artifacts are an art
treasure. While walking on a street you may see an old house, a mosque, an old
fountain or if you walk into one of the old palaces you can see a line or
a shape which will inspire you in jewellery design.
Let's draw first...
My favorite shape is tulip. You can find the tulip
everywhere you look. Below, you will see stilized tulip designs. We will take
fig. 2 to create a reticulated tulip brooch.
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Materials
First of all let us look at the materials for rendering a
design in colour.
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Medium thickness tracing paper (I use light tracing
paper for trials)
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mecanical pencil with a very sharp and hard (H2) lead
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Kneadable eraser
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Special pencil sharpener for sharpening the lead
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Coloured pencils
When we render the design we get the three
dimentional effect by using shading . When you design to show the
jewellery to your customer as close to real thing as possible or if you
design for a competition, your drawing and rendering will be like this but
if you design to give instructions to your bench jeweller your design should
carry all the information. All the measurements should include three sides, i.e.
from top, front and side.
When we touch the paper one side feels a
little rough the other side feels smooth. We use the rough side for colouring
with pencils the other side for painting with water colours.
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Yellow
metal
You see below the colouring, highlighting
and shadowing of a flat, a slightly curved and a domed metal. We assume the
light is coming from the top left corner.
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Flat, yellow
metal
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Slightly
curved yellow metal
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Domed,
yellow metal
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White metal
White metal is
coloured a little differently than the yellow. The colour of the paper (white)
is used for the metal's own colour. The highlights are done using the white
colouring pencil and shadowing is done either with the metallic pencil or with
gray colouring pencil.
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Flat,
white metal |
Slightly
curved white metal |
Domed,
white metal |
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Rendering
the tulip
The part of our tulip marked with x will be
domed shiny metal and the part marked with xx will be reticulated silver. If
you want you can use gold for domed part, but for the reticulated part I like to
use 800 karat silver.
We will design the domed part as yellow
metal and flat parts as white metal and we will give to it a textured look
to imitate the 'reticulated metal'.
We colour for the yellow metal very light
yellow.
The domed part gets
more light in this piece. Start highlighting the dome strongly from
the highest point and as you colour toward the edges lighten your grip on the
pencil.
We start highlighting heavily but before
coming all the way to the edge, the colouring ends. This way, we start giving
the domed effect to the design. We, then, start shading the places where there
is less or no light.
I use brown colouring pencil for shading
the yellow metal but you may change the brown's hue according the yellow metal's
hue. We will start shadowing from the edges (darkest part) and colour
towards the inside. Before touching the white highlights we should stop
colouring because a little bit of the yellow should be seen between the
highlight and shadow in the design.
The reticulated metal's texture rendered
like this; colour the metal, add the shadow and the highlight. Imitate the
wrinkled metal's texture by highlighting on the highest parts of the
little domes and shadowing on the hollow parts.
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Reticulation
We
will use 925 karat sterling silver for domed part of the tulip. We will polish our metal thorougly and then
we will have it gold plated or if we wish we can use gold for this part. The
part that we will reticulate will be 800-825 karat silver.
'Reticulation' is a metal texturing
technique which is done using the differences of silver's and copper's melting
points. First time it
was used in Russia by the Czar's jeweller Peter Carl Faberge.
We start preparing the metal; 800 part of
silver 200 part copper (or 825 silver - 175 copper) is melted and the ingot is
rolled to 1mm - 0.8mm. (18-20 gauge)sheet. If we intend to change the shape of
this metal later it will break therefore we should do this before the
reticulation.
The metal is heated until it shows a dark
red colour (not shiny). We quench it either in a heated solution of 10% sulfric acid
or in a unheated solution of 33% sulfric acid. By doing that we get rid of the
copper oxide which is accumulated on the surface.
(When you prepare acid solution always add
the acid to the water, otherwise it will splatter around)
After you repeat this heating and quenching
procedure 4 - 5 times there will be a pure silver layer on the surface of our
metal.
Place your metal on a clean soldering pad
and heat it with a torch which gives a neutralized flame.When you see the metal
turn dull red and start wrinkling, change the direction of your flame.Continue
this application until all your metal's surface is wrinkled. Do not hold
the flame on the surface until the metal is bright red. Because in that case you
have to start heating and quenching application all over again.
What happens here is that the inside of the
metal which has more copper melts before the surface which has high silver
content. While the melted metal expands and then cools down, the unmelted thin layer of silver
wrinkles.
When the metal cools down,
place your tulip
design on it and draw with a sharp point. Saw the tulip leaving a little
margin around the lines. You should cut the whole tulip design . (x
and xx parts)
Sterling silver sheet will be domed,
therefore it musn't be very thin. 0.40 - 0.45 mm. is a good thickness.
Draw the part which is marked x in the design to the metal and saw it leaving a
little margin around the lines. Put this metal up side down over a lead block
and give the dome shape by using doming tools. Use a piece of heavy paper
between the lead and the silver sheet to prevent the lead pieces to stick to the
silver. Because when heated during soldering, the lead particles melt and stick
the silver permanently.
To construct our tulip we solder the
domed leaves (x marked in the design) to the reticulated piece. File around the
shape very carefully. Now, you are ready to solder the findings of your brooch.
After polishing your tulip you have a beautiful brooch.
The point to take into consideration is;
the top layer of silver is thin therefore you must be carefull to file and
polish it. When soldering, be very carefull not to get the solder on the
reticulated metal.
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Today, I offered you just a drop of water
from the huge sea of knowledge ......
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