Above: (Crystalized native gold. Colorado Quartz Mine, Mariposa Co., California, USA. 3 x 1.75 x .25 inches (7.6 x 4.4 x .6 cm). Estimate: $30,000 - $40,000. Photo Heritage Auctions)
Some facts on Gold... because I love science and facts and its always good to learn new things! π
So, what is this stuff anyway? What really is this shiny ancient solid mineral substance that connects the gap between myth and science? It is the 79th element in the periodic table (Au), and is a noble metal. In its purest form, it is relatively unreactive and resists degradation by air, moisture, or acidic conditions. The element symbol for gold is Au. The symbol comes from the old Latin name for gold, aurum, which means "shining dawn" or "glow of sunrise" and in its most natural purest form is the only element which 'naturally' exhibits a golden reddish hue not derived from a chemical change.
The question of where elements like gold come from has been around for a long time. Though many scientists long argued that supernova explosions were the source, there is evidence that supernovas arenβt necessary. According to scientists and astronomers of the Harvard Astronomy Department, neutron star collisions produce all elements heavier than iron, such as platinum, palladium, mercury, lead and gold. They do it efficiently enough that they can account for all the gold that has been produced in the universe.
Gold has a melting point of 1,947.7 degrees Fahrenheit (1,064.18 degrees C) and a boiling point of 5,162 degrees F (2,850 degrees C). It has been mined around the world, and gold has been found on every continent except Antarctica!
Aside from its monetary, symbolic and decorative uses, it is used in electronics, electrical wiring, dentistry, medicine, radiation shielding, and even to color glass. It is used to coat astronaut helmets and microscopes and even to repair broken items like china vases. It is heavy and dense, but is also colourless, tasteless and pure 24k gold is non toxic and can be ingested and is frequently used in champagne and for embelishing desserts.
The rarest and most valuable form of gold is gold crystals. These can be worth as much as times as much as 100 times the price of gold bullion, and the price for nuggets is about 10 times that of bullion. And the value of crystals and nuggets does not fluctuate the way the price of gold bullion does!
Gold is the most malleable element. Malleability is a measure of how easily a material can be hammered into thin sheets. A single ounce of gold can be beaten out into a sheet that is 300 square feet. A sheet of gold can be made thin enough to be transparent. Gold is also extremely ductile. A single ounce of gold (about 28 grams) can be stretched into a gold thread 5 miles (8 kilometers) long and can even be used as embroidery thread.
Gold leaf is gold that has been hammered into thin sheets by gold beating and is often used for gilding. Gold leaf is available in a wide variety of karats and shades, the most commonly used gold is 22-karat yellow gold, pure 24k gold will have a golden yellow red tone. The art of gold beating is of great antiquity, being referred to by Homer; and Pliny states that 1 oz. of gold was extended to 750 leaves, each leaf being four fingers (about 3 in.) square; such a leaf is three times as thick as the ordinary leaf gold of the present time.
Layering gold leaf over a surface is called gold leafing or gilding. A primer base and size are laid and the gold is applied, gold dust and skewings are brushed away. Traditional water gilding is the most difficult and highly regarded form of gold leafing. It has remained virtually unchanged for hundreds of years and is still done by hand.
The term metal leaf is normally used for thin sheets of metal of any color that do not contain any real gold. Pure gold is 24 karats. Real yellow gold leaf is about 91.7% pure gold. The more silver the gold contains the whiter the colour will be. Silver colored white gold is approximately 50% pure gold. Keep in mind, pure 24k gold leaf will not tarnish. Mixed metal leaf, imitation leaf or 'composite leaf' is NOT edible and WILL tarnish and must be sealed.
Layering gold leaf over a surface is called gold leafing or gilding. A primer base and size are laid and the gold is applied, gold dust and skewings are brushed away. Traditional water gilding is the most difficult and highly regarded form of gold leafing involving the exacting science of making gesso and clay bole to the proper requirements for a superiour base and high burnishability of the gold. It has remained virtually unchanged for hundreds of years and is still done by hand. π
(Reference:
https://www.smithsonianmag.com/science-nature/all-the-gold-in-the-universe-could-come-from-the-collisions-of-neutron-stars-13474145/
https://en.wikipedia.org/wiki/Gold_leaf
https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Goldbeating)