Gold leaf - Important questions and answers
What is the difference between loose gold leaf and transfer gold? How do you recognize real gold leaf? And what does real gold leaf cost? Find out the answers to these and other interesting questions about gold leaf now.
What is gold leaf?
Gold leaf is a very thin gold foil made from either pure gold or a high-carat gold alloy. At the end of its production, gold leaf reaches a thickness of about 125 nanometers, which corresponds to 1/8000 millimeter.
Gold leaf with this thickness is also called single gold.
In addition to single gold, gold leaf is also offered as double or triple gold. This achieves a thickness of 220 nm and 330 nm. Due to its increased resistance, the double and triple gold is mostly used for exterior gilding.
What is gold leaf transfer?
Transfer gold, also referred to as storm gold, peel-off gold and gold leaf transfer, is particularly suitable for gilding smooth surfaces. During production, the gold leaf is pressed onto tissue paper. The transfer gold can then be placed directly on the surface to be gilded with the help of the tissue paper. After that, only the tissue paper needs to be removed.
What is loose gold leaf?
Unlike transfer gold, loose gold leaf is not pressed onto the tissue paper, but only sandwiched between tissue paper. As a result, the gold leaf cannot be placed in position with the fingers, but must first be cut to size on the gilding pad and then applied to the surface with the piecing brush.
How can gold leaf be recognized?
Gold leaf shines golden yellow when exposed to direct light. When backlit, it appears a greenish-bluish hue.
In addition to gold leaf itself, imitation gold leaf made of copper is now also available. These are significantly thicker than real gold leaf. To rule out the possibility that it is an imitation, the gold leaf should always be purchased directly from a gold leaf factory.
What does gold leaf look like?
Usually, the thin gold leaf sheets are offered with a gold leaf booklet in the format 80 x 80 mm. Depending on the type, the gold leaf can take on different colors. Commonly offered gold leaf colors include yellow, white, and citron.
Production of gold leaf
How is gold leaf made?
When looking at how gold leaf is made, there are many distinctive features. First, a pure gold bar weighing about 850 grams is melted down and shaped into the proper form. In the process, the gold bar is processed with the help of a roller in many operations to a thickness of only a few millimeters, until it finally becomes a strip of about 300 meters in length. Pieces are then punched out of the gold strip to form areas of equal size, stacked in powdered paper and placed in a book so that the gold flakes do not leave any residue. The stack is finally worked by a spring hammer for several hours at over 300 blows per minute until the square areas spread out over the paper. The piece of gold, which was still coarse at the beginning, may now be called gold leaf.
Where does gold leaf come from?
The production of gold leaf goes back 5000 years into the past. Even then, the coveted precious metal was traded and used in India and ancient Egypt. In Europe, the craft was finally learned and executed in monasteries during the Middle Ages. Finally, the gold beaters took over this special task. In the process, the Middle Franconian town of Schwabach was able to establish itself as a central location for this craft. Today, the majority of gold leaf is produced and distributed in factories.
Application of gold leaf
What can be gilded with gold leaf?
Especially in art, gold leaf is used to decorate objects such as picture frames, sculptures or even books. In architecture, gold leaf is also used to gild stucco and individual elements of buildings. Gold leaf is also used in gastronomy. There it is used to refine food and beverages.
Is gold leaf edible?
When refining dishes, the question naturally arises as to whether the gold leaf is edible. Since gold leaf itself is very thin and thus contains only an extremely small amount of the precious metal, it is considered safe to eat. Gold even has its own additive number: E175, which is also considered to be of no concern.
How to gild with gold leaf?
In addition to the gold leaf itself, you need some tools and aids to be able to gild objects.
In the first step, the surface to be gilded is cleaned and brushed with an application agent. The Cologne Instacoll system, which consists of two parts, is particularly suitable for this: The application agent itself and an activator. The lay-up agent is applied to the surface with a spray gun or brush. After one hour, the agent has dried and gilding can begin. The gold leaf is then applied in a period of another hour. If the gilding process takes longer than one hour or if it is to take place at a later time, the applied gilding agent can be reactivated with the help of the gilding activator.
With the help of the gilding knife, the gold leaf is taken from the gold leaf booklet and cut to size. In practice, the gold leaf is cut on the gilding pad with the gilding knife.
Afterwards, a special brush is needed, which is called a gilder. This is now electrostatically charged by running it once along the face. In the final step, the gold leaf is now picked up with the gilder and placed on the surface.
Cost of gold leaf
What does gold leaf cost?
The cost of gold leaf can be derived from the current gold rate. In recent years, the price of gold has ranged on average between 1400€ and 1800€ per troy ounce. This corresponds to a weight of 31.10 grams. The purity of the gold leaf also plays a relevant role in the costs. The higher the pure gold content in the gold leaf, the more the gold leaf is worth. Thus, the price of gold leaf is always based on the underlying gold price per troy ounce, the karat, and the amount of gold leaf desired.
How valuable is gold leaf?
As just described, the value of gold is composed of various factors. In addition to the pure material value of gold, the production of gold leaf must also be included in the price. For this reason, the price of gold leaf is higher than the actual material value.
In addition, gold leaf has another special feature. Unlike other raw materials, such as silver, gold lasts much longer in its condition. This is because gold does not oxidize. Thus, gold-plated objects are protected against external weather influences for decades, which in turn increases the value of gold leaf.
Interesting facts about gold leaf
When was gold leaf first used?
Gold leaf and its craft can look back on a long history. As mentioned above, 5000 years ago the first gold beaters in India made gold leaf. So it can be assumed that gold leaf was processed there for the first time. In Germany, gold leaf was used for the first time in the 16th century. At that time, the craft of gilding was mainly practiced in monasteries.
Where was the most gold leaf used?
Most gold leaf was and still is used in art and architecture. In the latter, there are some imposing buildings that stand out for their gilded elements.
For example, in Seoul there is the "63 Building", whose exterior facade is completely gilded. For the skyscraper with its height of 249 m and 60 floors, a total of about 5 kg of gold was used.
However, gastronomy is also enjoying gold leaf more and more. Here, the edible gold leaf is used especially for decoration and refinement of food and beverages.
More facts about gold leaf
It is amazing when you take a closer look at the dimensions of gold leaf and compare it with known sizes. With a thickness of about 125 nanometers, a leaf is barely visible to the naked eye from the side. By comparison, a hair, with a thickness of about 0.5 mm, is almost 4000 times thicker than gold leaf.
Already in the years around 1500, gold leaf was used to refine beverages. At that time, mainly schnapps, including the "Danziger Goldwasser", was refined with gold leaf flakes. This herbal liqueur is still available today.
The gold content itself is measured in carats. The purer the gold, the more carats it has. At most, gold can reach a carat number of 24, which corresponds to a gold content of 99.99%. One carat itself corresponds to a gold content of 4.167%. Gold leaf with 14 carats, for example, thus has a gold content of 58.5%.