Simply put, filigree is defined as metal work created by molding a length of wire, usually gold or silver, into an ornate pattern.
The definition given describes the original method for creating filigree, typical of antique jewelry. That technique would have been used to create the brooch pictured above. A jeweler would take a length of wire and mold it, soldering the wire at each connecting point in the pattern. This would have all been done by hand, no machines. Pieces made using this traditional technique are like small works of art and completely one of a kind.
The invention of the swing press allowed jewelers to recreate filigree designs on a mass scale. The swing press uses a heavy arm with a template attached. The arm presses the template down into a piece of metal, cutting the filigree pattern out. While this process isn’t as time intensive as the traditional method, it does achieve a similar look to handmade filigree.
With the invention of computer aided design (CAD), the swing press became mostly obsolete. A jeweler can use CAD to create a design that mimics the look of filigree in a piece of jewelry. Once the CAD design has been created, a model will be made using a 3D printer and the final piece of jewelry will be made from that 3D model. This method of creating a filigree design is the most cost effective, but some of the intricate detail is lost.