A burnisher is a tool used during the gilding process, it is rubbed over the gilded surface to polish the metal leaf causing it to increase it's gloss and shine. Traditionally a burnisher is made of a polished stone, these are still the most commonly used.

Burnishers are simple hand tools used to create mirror-like polish to gold leaf and other metal leaf gilded surfaces, they are an essential piece of gilding equipment. They can be made from metal, or polished gemstones such as:

• Agate Burnisher
  Agate is a type of quartz and is widely available as a polishing stone but it has the disadvantage of absorbing moisture from the atmosphere. Pencil and dog-tooth burnishers made of agate are perfectly adequate for almost all gilding projects and a the easy choice for a beginner.
   
• Psilomelanite Burnisher
  A widely used burnisher because it has comparatively few flaws and is less wasteful in manufacture process than hematite and for this reason it is also a little cheaper to buy.
   
• Hematite Burnisher
  Known to be the best type of burnisher it is a high-grade iron ore. Hematite looks black, but is actually a red stone and is commonly called bloodstone. It remains dry even in humid conditions, and skates over the metal lead while creating a brilliant gleam. It also disperses static so gold does not readily stick to it.

Burnishing tools range in size and each one is used according to the surface that is being gilded. In regards to shape, there are three main shapes; flat, toothed and pencil. For example a large area may require a large flat burnisher, and a fine detailed sculpture may require a small 'dogs tooth' burnisher. 

How to burnish metal leaf:
Before using your burnisher breathe on the burnisher and polish it with a cloth used to clean eye glass lenses, or a piece of silk. It should be kept immaculate at all times. Use a burnisher with slow actions, and gentle pressure, using gentle but swiftly motioned strokes about an inch or so wide. The correct amount of pressure comes with practice and experience. Too little pressure will not produce a high gloss surface and too much pressure will begin to rub off the leaf!

Caring & Storing your burnisher tool: 
Burnishers are fairly delicate and can chip easily if mistreated. Keep them smooth and in good condition by rubbing them on the flesh side of a piece of high quality fabric coated with whiting, or, if the burnisher is old and needs renewing, restore it by rubbing on a zinc-lined board coated with a small amount of flour or emery mixed with a small portion of machine oil.

Always store the burnisher in a soft cloth or felt pouch, never store it openly with other tools & equipment, never leave it lying on the desk, even tiny scratches will gradually build up and overtime this may cause the burnisher to "pull." at the gilded surface.