Platinum Group Metals
Also: PGM, Platinum Metals, Platinum Group
Platinum Group Metals (PGM) are six chemically related transition metals – platinum, palladium, rhodium, iridium, osmium, and ruthenium – distinguished by exceptional corrosion resistance, high melting points, and catalytic properties.
Platinum Group Metals (abbreviated PGM) form one of the most valuable and rarest groups of metals on Earth. They comprise six elements that are adjacent in the periodic table and exhibit nearly identical chemical behaviour: platinum (Pt), palladium (Pd), rhodium (Rh), iridium (Ir), osmium (Os), and ruthenium (Ru). Due to their scarcity, industrial importance, and price dynamics, PGM are of global interest both as investment assets and as indispensable industrial raw materials – current prices for platinum and palladium are available here in real time.
The Six Platinum Group Metals at a Glance
| Metal | Symbol | Atomic Number | Density (g/cm³) | Melting Point (°C) | Primary Use |
|---|---|---|---|---|---|
| Platinum | Pt | 78 | 21.45 | 1,768 | Catalysts, jewellery, fuel cells |
| Palladium | Pd | 46 | 12.02 | 1,554 | Autocatalysts, electronics, hydrogen technology |
| Rhodium | Rh | 45 | 12.41 | 1,964 | Three-way catalysts (NOx reduction) |
| Iridium | Ir | 77 | 22.56 | 2,446 | Spark plugs, crucibles, electrodes |
| Osmium | Os | 76 | 22.59 | 3,033 | Hardening additive for alloys, scientific research |
| Ruthenium | Ru | 44 | 12.45 | 2,334 | Hard disk coatings, electronics, catalysis |
Osmium, at 22.59 g/cm³, is the densest naturally occurring element of all – roughly three times heavier than iron.
Occurrence and Production
PGM occur extremely rarely in the Earth's crust; their average concentration is in the low ppb (parts per billion) range. Around 70–75% of global PGM production comes from South Africa, primarily from the Bushveld Igneous Complex in Limpopo Province – one of the geologically most remarkable ore deposits on Earth. Other significant producing countries include Russia (particularly Norilsk for palladium), Zimbabwe, and Canada.
Extraction occurs predominantly as byproduct mining during nickel and copper production. Ore grades typically amount to only a few grams per tonne of rock, making mining laborious and cost-intensive. The raw ore first yields doré bars, which are subsequently refined in refineries.
In addition to primary mining, recycling (particularly from autocatalysts and electronic scrap) plays a growing role; for palladium, secondary material already covers a considerable share of demand.
Industrial Significance
The single most important application for platinum, palladium, and rhodium is the automotive exhaust catalyst. Three-way catalysts convert carbon monoxide, unburned hydrocarbons, and nitrogen oxides into less harmful compounds – without PGM, this process would not be economically viable.
Further key applications:
- Hydrogen technology: Platinum is the central catalyst in proton exchange membrane fuel cells (PEM-FC), giving PGM particular attention in the context of the energy transition.
- Electronics: Palladium in multi-layer ceramic capacitors (MLCCs), ruthenium in hard disk coatings.
- Chemical industry: Platinum and palladium as catalysts in nitric acid and sulfuric acid production.
- Medical technology: Platinum in pacemakers, electrodes, and implant materials.
- Jewellery: Platinum (especially in Japan and the luxury segment) and palladium as a white gold substitute.
Price Formation and Investment Aspects
Unlike gold or silver, PGM prices are primarily driven by industrial demand. Rhodium, for example, can experience extreme price swings – it traded at over 20,000 USD per troy ounce between 2020 and 2021, but subsequently fell dramatically. The high price volatility reflects the tight, geographically concentrated supply structure and the sensitive dependence on the automotive market.
Investors have the following investment forms available: physical bars and coins (e.g. platinum coins), physically backed ETCs, and certificates. The tax treatment (speculative holding period, VAT on silver versus tax exemption for investment gold) differs depending on the metal and jurisdiction – this is not tax or investment advice. Historical price developments can be tracked under Historical Precious Metal Prices.
Distinction: PGM vs. Other Precious Metals
Although gold and silver are regarded as the best-known precious metals in everyday usage, they are not part of the platinum group. Compared to gold and silver, PGM are characterised by even higher melting points, greater hardness, and significantly more pronounced catalytic activity. What all precious metals share is corrosion resistance to air and water as well as resistance to most acids – however, PGM dissolve in aqua regia.
In Brief
Platinum Group Metals are indispensable industrial raw materials with a highly concentrated supply and price-determining demand from the automotive and technology industries – their scarcity and versatility make them a significant, yet price-volatile, segment of the precious metals market.