Key Differences In Gold, Silver, Platinum And Palladium

Gold, silver, platinum, and palladium are all used as investment vehicles, but key differences in their characteristics determine their overall demand. Gold is primarily used for jewelry and as a financial asset, while platinum and palladium see most of their demand as an industrial metal. Silver has both investment and industrial uses, which exposes it to economic conditions in both sectors.

This article will examine the characteristics that set these four metals apart and the role they play in their demand.

Physical Properties Of Precious Metals

Gold

Gold is noted for its non-reactivity to most solutions and acids, being the second-least reactive metal behind platinum. It is also noted for its reflectiveness and its high electrical and thermal conductivity. Gold is the third-best conductor of electricity, behind silver and copper. Gold does not tarnish or corrode. Its extreme malleability allows it to be stretched or hammered to a less than one micron thickness. It has been stretched into a monatomic wire in the laboratory. Gold is often found in pure form, as nuggets or veins.

Silver

Silver has the highest electrical and thermal conductivity of any metal. It has approximately the same softness as gold. Silver is the only precious metal that tarnishes. It has the highest reactivity of the four precious metals but less than copper or iron. Silver has long been noted for its antibacterial properties. Silver has the highest reflectivity of any metal, making it the preferred substance for making mirrors and optics.

Platinum

Platinum is the densest of precious metals, with a density higher than iron. It is the third-hardest precious metal. Platinum is extremely heat-resistant, with a melting point of 1,768.2℃ (3,214.8℉.) It has the lowest reactivity of any metal yet becomes an essential catalyst in industry and automotive catalytic converters once heated to high enough temperatures. Platinum is one of, if not the most ductile metal, leading it to be used where very thin, tough, but flexible wiring is required.

Palladium

Palladium is the least dense of the Platinum Group Metals. It is not as heat resistant as platinum (melting point: 1554.9℃/2,830.8℉), but its chemical properties at high temperatures make it an excellent catalyst in automotive catalytic converters. One notable property of palladium is its ability to purify hydrogen.

Quick Facts of Precious Metals

Softness / Malleability

The malleability/softness of a precious metal describes the ease with which it can be worked. The following chart ranks the hardness of gold, silver, platinum, and palladium according to the Mohs scale. Copper and iron are included as references.

• Gold. 2.5
• Silver. 2.5
• Copper 3.0
• Iron 4.5
• Platinum 4.6 to 5.0
• Palladium 4.75

Density (g/cm3)

The density of precious metals correlates to their malleability and chemical reactivity. Copper and iron are included as references.

• Gold 19.32
• Silver 10.49
• Copper 8.96
• Iron 7.87
• Platinum 21.45
• Palladium 12.02

Conductivity

Conductivity is an important property of precious metals, especially in low-voltage situations such as microelectronics. These are the rankings of the precious metals compared to all elements. Copper and iron are included as references.

• Gold #3
• Silver #1
• Copper #2
• Iron #18
• Platinum #19
• Palladium #20

Reactivity

Chemical reactivity affects the purposes for which a metal can be used. All four precious metals are hypoallergenic in a pure state. These are the precious metals ranked by decreasing chemical reactiveness. Copper and iron are included as references.

• Iron
• Copper
• Silver
• Palladium
• Gold
• Platinum

Precious Metals Demand

Investment Demand

Gold and silver’s rarity and beauty made them the major vehicles for storing and transferring value for thousands of years. Until the 20th century, they were both literal money. Both are soft and malleable, making them easy to work with when making bars and coins.

On the other hand, platinum and palladium weren’t refined until the 19th century. Refining them is difficult and expensive. Investment platinum and palladium bars are niche products, even though platinum is the second-most expensive precious metal. Retail investors will find it difficult to find a buyer when they want to sell.

Jewelry Demand

Jewelry accounts for around half of global gold demand each year. Jewelry is one area where the softness of pure gold and silver is a handicap. Both are alloyed with small amounts of other metals to reduce damage and improve scratch resistance.

Platinum is harder and denser than gold, making for more durable jewelry. Palladium jewelry has the same benefits as platinum, but its lower density makes for more lightweight jewelry. Neither metal tarnishes like silver.

Industrial Demand

Half of annual silver demand is for industrial uses. Silver is the world’s most conductive metal, making it the preferred metal for batteries, solar panels, and electrical circuitry. Its high reflectivity is essential for mirrors and optics. As solar demand increases, so does the demand for silver.

Gold is the third-most reflective metal, behind silver and copper. Because it doesn’t tarnish, it is used to protect silver and copper wires from oxidation. Its extreme ductility, resistance to tarnish, and high conductivity make gold the metal of choice for microcircuits and electrical connections in adverse conditions and difficult-to-reach places.

The automotive industry accounts of most of platinum and palladium’s demand. Their efficiency as chemical catalysts and high melting points make them indispensable parts of catalytic converters.

Platinum is used in the same way in the pharmaceutical and petrochemical sectors. Its hardness, ductility, and resistance to corrosion have led to its use in heavy-duty and industrial electrical contacts where silver or gold parts would wear out or break.

Palladium’s unparalleled ability to filter and purify hydrogen makes it a major component in industrial hydrogen production and in hydrogen fuel cells. It is also a major component in catalytic converters. Swinging price differences between platinum and palladium over the last couple of decades have led automakers to use whichever of the two is the cheapest to make catalytic converters for all engines.

Medical

Precious metals have many medical uses besides dentistry. Gold salts have long been used to treat rheumatoid arthritis. Radioactive gold nanoparticles are used to find and noninvasively treat cancer. Gold sees widespread use in rapid testing kits which have been credited with helping control outbreaks of diseases such as malaria.

Silver’s anti-bacterial properties are used to treat wounds and prevent infections. It is used to plate medical instruments such as breathing tubes and catheters to prevent infection. It is widely used in bandages, wound dressings, and anti-bacterial ointments. Silver is also used in making both large and portable water filtration systems.

Platinum and gold are both used in plating stents that support weak blood vessels and for pacemaker wires. Platinum is often used as a biologically inert plating for hip replacements and artificial knee joints. Palladium can be used interchangeably with platinum in these cases, though platinum remains the default choice of the two due to its familiarity with surgeons.