Etching

Etching is a process when the metal is eroded using acid bath and then inked. It is a common technique used by the fashion jewelry makers.

Process
The metal plate than can be aluminum, zinc, silver copper or any other metal is cut into the required shape.

First an acid resistant material is applied to the metal piece to be etched. The required image is then cut into the resistant layer, using needle and other tools. The plate is then dipped in the acid bath. Generally a Nitric Acid bath is used for the purpose. The exposed metal part is bitten by the acid. The temperature of the acid bath and the time for which the plate is dipped, determine the depth of the etching. The plate is removed from the bath once the metal is etched to the required state.

Care should be taken to cover the backside of the metal plate with the acid resistant or a plastic tape. The metal plate should be clean and without scratches. The key to a classic pattern is the skill in scratching the acid resistant layer and the time for which it is dipped in acid bath. The longer in acid, the deeper the line and the darker it will print. Finally the ground layer is removed and the plate is inked.

The etching ground is formed in different ways. The types of etchings get their names from the ground making technique. Hard ground and soft ground are used to make lines, and an aquatint ground is used for tones. Each gives a different finish. Grounds for line drawing are usually made of wax.

In hard ground etching the artist draws through a hard wax covering the plate. The lines thus created are usually thin, wiry, and blunt at the ends.

In soft ground etching the lines look like pencil or crayon lines, and are made by drawing on a piece of paper that covers a soft wax coating on the plate. When the paper is lifted off, it removes the wax where the pencil pressed, but some wax stays in the lines in the pattern of the paper grain.

Very fine work can be created using this technique the patterns can be raised or recessed as per the image carving. Line drawings of flowers, animals and tribal art on pendants, earrings and bracelets are the motifs in vogue. Emblems and logos on badges and belts etc are often done using this technique.

Photo Etching is a process where more refined images, even photographs can be etched on the metal. This is done for customized jewelry and other products or where the exact image has to be reproduced time and again.

Here the metal plate is covered with a light-sensitive acid-resistant base. It is then exposed to a photographic image. The Negative Resist dissolves in the area exposed to light and hardens in the remaining. The plate is then etched and treated to the positive resist to remove the ground.