How to different between Platinum and Palladium
Platinum and palladium are both precious metals that are often used in jewelry, industry, and as investment commodities. Though they appear similar and belong to the same group of metals in the periodic table (the platinum group metals), there are several ways to differentiate between them. Here are some key differences:
Physical Properties:
Color: Platinum is naturally white with a grayish hue, whereas palladium is also naturally white but tends to have a slightly darker and grayer appearance than platinum.
Density: Platinum is denser than palladium. Platinum has a density of about 21.45 grams per cubic centimeter, whereas palladium has a density of about 12.02 grams per cubic centimeter. This means that a piece of platinum jewelry will feel heavier than a similar piece made of palladium.
Chemical Properties:
Corrosion Resistance: Both metals are highly resistant to corrosion and oxidation. However, platinum is slightly more resistant to corrosion under extreme conditions compared to palladium.
Melting Point: Platinum has a higher melting point (1,768°C) compared to palladium (1,554°C). This characteristic is more relevant to manufacturing and processing than to everyday use or identification.
Market Value and Price:
Historically, platinum has been more expensive than palladium. However, their prices can fluctuate due to market demand, availability, and economic conditions. As of the last few years, palladium has often been priced higher than platinum, primarily due to its increased demand in automotive catalytic converters.
Uses:
Catalytic Converters: Both metals are used in catalytic converters, but palladium has become more popular for gasoline engines due to its efficiency and lower historical cost.
Jewelry: Platinum is often preferred for fine jewelry due to its density and durability. It is especially popular for settings in diamond rings because it holds stones securely and its color enhances the brilliance of diamonds.
Investment: Both metals are available in the form of bullion coins and bars for investment purposes.
Testing and Identification:
Acid Test Kits: Specialized test kits can help identify and differentiate platinum from palladium through chemical reactions that indicate the specific metal.
X-Ray Fluorescence (XRF): This non-destructive technique is often used by professionals to determine the exact composition of metal items, including distinguishing between platinum and palladium.
Hallmarks:
Jewelry made from these metals will often have a hallmark stamp indicating its composition. Platinum might be marked as "950 Plat" or "Plat," indicating that it is 95% pure platinum. Palladium might be marked as "950 Pd," indicating 95% purity.
When trying to differentiate these metals in jewelry or other items, using a combination of these factors, especially professional testing for conclusive identification, is recommended.
