Interesting Engineering posted an article in its Science section as to the Top 10 most valuable precious metals. Can you guess them all? I bet you surmised that silver and gold would be at the top, but you may not have even heard of the others, like osmium and indium. According to Lara Lopes, the author of the article:
Rarity alone isn’t enough to qualify a metal as precious. It must also be naturally occurring, lustrous and ductile, possess a high melting point and low reactivity and, most important to anyone wishing to wear jewelry made from the metal, it must not be radioactive. All of these factors contribute to a metal’s value and cost per gram isn’t necessarily the best indicator of how valuable the metal is to the human race.
According to Lopes, here are the top 10 precious metals, and a brief explanation of why they made the list. For more details and full explanations, go to http://interestingengineering.com/top-10-most-valuable-precious-metals/ [Editor’s Note: This article is no longer available on the Interesting Engineering site]
- Gold: Gold’s desirable properties, broad scope of functioning uses, history within finance, and popularity in jewelry all contribute to its position as the most valuable precious metal to mankind.
- Rhodium: A member of the platinum group of metals itself, rhodium is most commonly found mixed with other platinum group metals. This makes it difficult to extract, which can only increase its value.
- Platinum: Platinum is considered a noble metal and has made a name for itself through its malleability, density and non-corrosive properties.
- Ruthenium: Ruthenium has become quite popular in the electronics field, as a way to effectively plate electric contacts.
- Iridium: This whitish metal has a super high melting point, is one of the densest elements around and stands as the most corrosion-resistant metal.
- Osmium: This very hard, brittle metal has an extremely high melting point and is used to harden platinum alloys for electrical contacts, filaments and other uses.
- Palladium: Automobile makers rely on it for their catalytic converters to reduce emissions and is used heavily in electronic applications.
- Rhenium: Rhenium is used in high-temperature superalloys that are employed to make jet engine parts, by means of 70% of the universal rhenium productions.
- Silver: This element has great electrical and thermal conductivity, as well as the lowest contact resistance of all the metals.
- Indium: During World War II, it was used as a coating for bearings in aircraft engines, but it can also be used to create corrosive-resistant mirrors, semiconductors, alloys and electrical conductivity in flat-panel devices.
Prices of these precious metals can average over $1,000 per ounce, and some of these metals are very rare but in high demand for use in our everyday lives. So it is important that any metals used in the various applications above be analyzed for their purity. If the metal is misidentified or alloyed with the wrong metal, the results may be disastrous. Something as small as a metal fastener, alloyed with the wrong material, can cause accidents to happen in the automotive and aerospace industries. If a rhenium supply had contaminants and was used to make a jet engine part, there could be a risk to all the passengers. The six platinum group metals (PGMs), — composed of platinum (Pt), palladium (Pd), rhodium (Rh), iridium (Ir), ruthenium (Ru) and osmium (Os) — are instrumental in healthcare and life-saving medical devices and implants so the raw materials used in these items need to be verified before being placed in a human body. Even contaminants in silver can adversely affect the quality of jewelry, as well as health. What if the silver was mixed with a toxic element?
Throughout the precious metal life cycle – from refining to recycling – the goal is always to ensure quality, control costs, and achieve accurate purity analysis. With the volatility and high price of precious metals, even a small variation in composition accuracy can be expensive. X-ray fluorescence (XRF) analyzers help provide reliable analysis – and unlike other testing methods, are completely nondestructive. They can test the purity and chemistry of all precious metals, including chemical analysis of tramp and trace elements, which could impact valuation and future refining needs, as well as safety.