So first of all what exactly is Filigree?

Filigree is a technique for creating simple or elaborate designs from square, rectangular, twisted, round, or beaded wire. It can be combined with other techniques, like granulation. One of the most important characteristics of filigree is the use of sweeping spiraling designs. It is possible to do straight geometric forms with filigree, but traditionally this is much less common.

This picture of a decorative dish that was created with filigree shows the amazing complexity that is characteristic of traditional style filigree work.

English: Dish, Filigree work (Photo credit: Wikipedia)

Filigree can be used to create the entire piece, or just as a surface treatment on a piece of jewelry or sculpture. The technique has been used for thousands of years. The Greeks had developed this technique to a high art by 350 BC. This picture shows filigree, used as a surface decoration on a piece of sculpture from the Tang Dynasty (618 – 907 AD).

English: Tang Dynasty figurine horse with gilded filigree (Photo credit: Wikipedia)

Filigree was traditionally executed in gold or silver. Modernly it is usually done in gold, silver, or nickel silver, but technically it could be done using any metal that can be soldered or welded together.

Filigree work can be flat or very three-dimensional. The modern sculptural miniature in this picture is an excellent example of the versatility of filigree as an art form.

How is Filigree created? The technique varies slightly depending on whether it is being used as a stand-alone form, or a surface treatment. If filigree is used as a stand-alone form, care must be taken to the make the piece structurally stable.  The wire is carefully formed using fingers and pliers. The pieces of wire are placed together so that they touch. Care should be taken to create a fairly compact form, with no loose coils that might tend to catch on hair or clothing. The individual coils are placed so that they touch. Then flux and solder are applied, and the piece is soldered together.

If the filigree is being used as a surface treatment, the base piece of metal is created first. Once the base piece exists, the filigree is placed on the surface and soldered in place. The major concern is making sure that the filigree is solidly attached to the surface with no loose pieces or pieces that stick out that would snag on things.

Filigree that is used as a surface decoration relies on the piece it is soldered to for structural stability. The form can be as simple as a circle or as complex as the most elaborate spiral flourish.

The gold piece in this picture uses a gold sheet that has been formed with chasing and repousse as it’s structural base. Beaded wire, and spiraled wire (formed into a circle around the center of the largest flower) are combined with granulation and other forms to create this elaborate design.

I hope that this brief blog gives you a basic understanding of the technique of filigree and the complexity of the design and assembly process.

Next time: Overlay

My first thought when I went to start this blog was that Granulation is magical and amazing. Now I realize that this is obviously an overstatement to most people, but understanding the process makes the sentiment correct for me. Granulation is a surface decoration technique that uses tiny granules (spheres) of  metal that are soldered, fused or eutectic soldered to the metal surface in patterns. The technique has been used for thousands of years and was probably invented by the Sumerians. Granulation was usually done in gold, although it is possible to do it with silver.

Gold serving Bowl with Pulviscolo Granulation Etruscan 7th century BCE (Photo credit: mharrsch)

OK, so what is the difference between soldering, fusing, and eutectic soldering?

Soldering actually involves adding a lower melting temperature metal alloy (solder) to the surface of a metal piece and melting the metal alloy to hold two pieces of metal together. A chemical solution called flux allows the solder to flow into the tiny gaps between the metal, fill them and join the pieces of metal together. This technique is difficult to use with complex granulation designs because not all of the granules will solder at the same time and if you repeat the process some of the granules usually fall off. You also usually wind up with large puddles of extra solder on the surface of the piece in order to make the granules stick.

Fusing involves using granules and a metal surface that are made of the same metal alloy. The alloy is usually either fine silver (99.9% pure silver) or gold with a purity of at least 18k. The granules are temporarily glued in place with a special diluted flux and then the piece is heated in an oven until the surface just starts to melt. When the piece comes out of the oven the granules are fused to the surface of the metal piece and the flux has burned away. Modernly this process can also be done using electricity, which causes the granules to fuse to the metal piece without additional heat.

Eutectic soldering uses a special combination of plant gum and copper salts to glue the granules to the metal piece. When the metal is heated, the copper salts lower the melting point of the granules and the metal piece that they are glued to. This causes them to fuse together just where the granules touch the metal surface. The result is a very sturdy but neatly connected design.

I hope that this blog gives you a basic understanding of the process of granulation.

Next time: Filigree

Gold pin with a Mistress of the Animals (potnia theron). Gold with granulation, ca. 630 BC. (Photo credit: Wikipedia)

A lot of traditional craft jewelry is made with a technique called soldering. Most Southwestern Native American jewelry is soldered. But what exactly is soldering?

Soldering is a technique for joining two or more pieces of metal together using a melted metal alloy, called solder. The solder must melt at a lower temperature than the two pieces of metal that are being joined together. There are many different types of solder. Every type of metal has recommended types of solder. The goal is usually to match the color of the solder to the color of the metal, so that it doesn’t show when the piece is finished. It is also important to realize that some types of solder can damage specific metals – for instance solder with lead may be silver colored, but it will actually corrode Sterling Silver.

Once you have the appropriate solder for your metal you need to sort your solders by the temperature that they melt at. Solder comes in different temperature ranges for a very important reason. A lot of times when a piece is being assembled it needs to be soldered several times. The soldering process needs to be planed so that you start with the highest temperature solder and progress to the lowest temperature solder. That way you will not accidentally melt the previously soldered joints.

The other major ingredient that is necessary for soldering is flux. Flux keeps the metal clean while it is being heated and can also be used to help direct the flow of the solder.

The basic soldering process goes like this. Clean the pieces of metal that are going to be joined. Make sure that the surfaces that you want to join are smooth and meet up very closely, with no light showing between them. Put flux between the two pieces of metal and place tiny pieces of solder tightly up against the edge of the piece that is being soldered on.

This graphic shows the basic set-up for soldering a piece.

So we have discussed solder and flux, but we have ignored a VERY critical part of the soldering process – heat. In order to solder we need a source of heat to melt the solder. The most commonly used sources of heat are an oven or a torch.

The type of oven that can be used for soldering is called a kiln. Whether it is gas or electric, the most important thing is that the temperature control on the kiln be accurate. You want to be able to solder without melting the piece.

The most commonly used type of torch used for jewelry work is probably the oxy- propane torch. This torch uses a tank of oxygen and a tank of propane, hooked together with a special pressure regulator. The pressure that you use and the size of the tip on the torch control the temperature of the torch. It is then up to the operator to make visual judgments about the progress of the soldering process and know when to move the torch, or remove the heat completely.

Soldering definitely takes some practice, but it is one of the most commonly used techniques in jewelry manufacture and it is very important to at least understand how the process works.

Next Time: Granulation