Platinum is not a type of gold, but rather an entirely separate metallic element with its own unique characteristics. The common confusion stems from both metals being classified as precious metals due to their rarity, high value, and resistance to corrosion. Although they are often used in similar luxury and industrial applications, gold and platinum are fundamentally distinct substances.
Elemental Classification: Gold vs. Platinum
Gold (Au) and platinum (Pt) are distinct elements on the periodic table. Gold has an atomic number of 79, while platinum has an atomic number of 78. This difference means a gold atom contains one more proton in its nucleus than a platinum atom, which is the definitive factor separating the two elements.
Both metals are classified as transition metals, which places them in the same general family of elements known for their ductility and conductivity. Despite this broad grouping, the variation in their electron configurations prevents them from sharing chemical properties beyond their general metallic nature. Gold and platinum cannot be chemically converted into one another, solidifying their separate identities.
Key Differences in Physical Properties
The most noticeable physical difference is the natural color and luster of the pure metals. Gold is known for its distinct metallic yellow color, whereas pure platinum presents a silvery-white or gray appearance. This innate color difference is why gold jewelry is typically yellow, and platinum jewelry is naturally white, without needing the rhodium plating often applied to white gold.
Platinum is significantly denser than gold, which is a major factor in the feel and weight. Platinum’s density is approximately 21.45 grams per cubic centimeter, making it about 11% denser than gold’s 19.32 grams per cubic centimeter. A piece of platinum jewelry will therefore feel heavier than an identical piece made from 18-karat gold.
Platinum also possesses a much higher melting point of 1,768 degrees Celsius, compared to gold’s 1,064 degrees Celsius. This higher thermal resistance makes platinum more difficult to work with in manufacturing but contributes to its remarkable durability. Furthermore, platinum is highly inert, exhibiting the lowest reactivity of any metal, which gives it an exceptional resistance to tarnishing and corrosion.
Practical Applications and Market Value
The way each metal is measured for purity reflects their different uses and properties in the jewelry trade. Gold purity is measured using the karat system, where 24-karat represents 99.9% pure gold, and jewelry is commonly 14-karat or 18-karat due to the softness of the pure metal. Platinum jewelry, conversely, is almost always alloyed to a very high standard, typically containing 90% to 95% pure platinum, indicated by a “950” stamp.
Their differences in strength and thermal properties also dictate their application in high-tech fields. Platinum is heavily used in the automotive industry for catalytic converters, which leverage its catalytic abilities to reduce harmful emissions. It is also employed in medical devices like pacemakers and in chemotherapy drugs due to its biocompatibility and resistance to bodily fluids.
Gold, in contrast, is primarily valued for its conductivity and resistance to corrosion, making it a fixture in electronics, such as connectors in computers and smartphones. While platinum is significantly rarer than gold, its price can be more volatile because its demand is heavily tied to industrial production, especially the automotive sector. Gold’s price is often more stable, as it is viewed more broadly as a traditional store of wealth and an investment hedge against economic uncertainty.