Most people think of gold as a precious metal that is used mostly in jewellery because of its sparkle and shine. For others, however, gold is a marvel material that allows us to live modern lives!
All Waste Maters measures, melts, and recycles gold from many sources every day. We are familiar with its unique characteristics as well as its uses.
These are our professional opinions on why we think gold is so extraordinary.
Plasticity
Gold is a soft yellow metal that has a beautiful sheen. It is one of the most malleable, ductile elements. It can be rolled into semitransparent sheets, and it is so malleable it can be pulled into small enough wires to be used in semiconductors. A single ounce (28g) can be beat out to 300 sq. feet. Gold could be described as the Play-Doh for metals.
Conductivity
The conductivity of heat and electricity is excellent in gold. Silver is the most reflective precious metal and has the highest thermal conductivity. Silver is the most efficient conductor of all metals, but copper and gold are more commonly used in electrical applications due to their lower prices and higher corrosion resistance. Because gold is non-corrosive and can be molded to any shape, it’s used in electrical connectors for all kinds of devices.
Reactivity
The Periodic Table has gold as one of the least reactive elements. It does not react with oxygen so it doesn’t rust or corrode. It is inert to water, air, alkalis, and any acids, except aqua regia, which is a combination of hydrochloric and nitric acids, and can dissolve gold. Our acid assays are accurate because of its acid resistance. It can react with halogens. For example, it will react slowly with room-temperature chlorine gas to form AuCl3. Gold chloride can be heated gently to decompose and release its pure elements. It is resistant to all bases, except potassium cyanide. Energy Reflectance Surface reflectance is the material’s ability to reflect radiant energy. It refers to the percentage of incident electromagnetic power that is reflected on an interface. The electromagnetic radiant energy reflected by gold is good, as it can reflect radio waves, infrared and ultraviolet radiation. Its unique optical properties, as well as its resistance to any attack and ability to be applied in very thin films make it an ideal material for a variety of industries. Gold is used to protect satellite components and space suits in aerospace applications.
We deal in high volumes of precious metals of all shapes, weights and purity. Our technologies allow us to use multiple types of assays in order to verify the melt-value of any customer’s products.
There are several easy and quick ways to distinguish alloy from pure gold.
Discoloration: While pure gold is not susceptible to tarnish, it can be a sign of discoloration. Fake gold can be revealed even by slight color variations.
Magnets: Like most precious metals, gold is not magnetic. The magnet may react to the item in question. This could be an indication that the iron, nickel, or other ferromagnetic materials have been added to the gold, resulting in a lower karat.
Scratching: A simple scratch test can reveal many kinds of fake gold even without acid. You can perform a Porcelain Scratch Test by using a ceramic plate or unglazed tile and scratching the object. If the item leaves a black streak, it is likely not to be gold. The item will likely be considered gold if the streak is of a gold colour. It may scratch the item, but not much.
Float test: Drop the item in a glass full of water to check its buoyancy. While real gold will sink due to its density, many alloys can float. If your piece rusts or discolours, it is likely that it has been plated or fake. This test is easier on smaller samples like jewellery and alluvial flake. You should be aware that metals made to look like gold can still sink. Therefore, even if the piece passes this float test, it is worth performing additional tests.
It is always a good idea for you to seek specialist advice if you are unsure. All Waste Matters has over 50 years experience in recovering gold from many industries. We have a wide range of techniques and methods to recover it.
