Platinum Group Metals
Also: PGM, platinum metals, platinum group
The platinum group metals (PGMs) 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 (PGMs for short) form one of the most valuable and rarest metal families on earth. They comprise six elements that sit side by side in the periodic table and behave almost identically in chemical terms: platinum (Pt), palladium (Pd), rhodium (Rh), iridium (Ir), osmium (Os) and ruthenium (Ru). Because of their scarcity, their industrial importance and their price dynamics, PGMs are of global interest both as investment assets and as indispensable industrial raw materials – live prices are available for platinum and palladium in real time.
The six platinum group metals at a glance
| Metal | Symbol | Atomic number | Density (g/cm³) | Melting point (°C) | Main use |
|---|---|---|---|---|---|
| Platinum | Pt | 78 | 21.45 | 1,768 | Catalysts, jewellery, fuel cells |
| Palladium | Pd | 46 | 12.02 | 1,554 | Autocatalysts, electronics, hydrogen tech |
| 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, science |
| Ruthenium | Ru | 44 | 12.45 | 2,334 | Hard-disk coatings, electronics, catalysis |
At 22.59 g/cm³, osmium is the densest naturally occurring element of all – roughly three times heavier than iron.
Occurrence and extraction
PGMs occur extremely rarely in the Earth's crust; their average concentration lies in the low parts-per-billion range. Around 70–75 % of the world's PGM output comes from South Africa, above all from the Bushveld Igneous Complex in Limpopo province – one of the most geologically extraordinary deposits on earth. Other significant producer countries are Russia (particularly Norilsk for palladium), Zimbabwe and Canada.
Extraction happens predominantly as by-product mining alongside nickel and copper. The ore grade is typically only a few grams per tonne of rock, which makes extraction laborious and costly. The raw ore first yields doré bars, which are then refined at dedicated refineries.
Alongside primary mining, recycling (especially from autocatalysts and electronic scrap) plays a growing role; for palladium, secondary material already covers a considerable share of demand.
Industrial importance
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 PGMs this process could not be realised economically.
Other key applications:
- Hydrogen technology: platinum is the central catalyst in proton-exchange-membrane fuel cells (PEM-FC), giving PGMs particular attention in the context of the energy transition.
- Electronics: palladium in multilayer capacitors (MLCCs), ruthenium in hard-disk coatings.
- Chemical industry: platinum and palladium as catalysts in nitric-acid and sulphuric-acid production.
- Medical technology: platinum in pacemakers, electrodes and implant materials.
- Jewellery: platinum (especially in Japan and the luxury segment) as well as palladium as a white-gold substitute.
Price formation and investment aspects
Unlike gold or silver, PGM prices are driven primarily by industrial demand. Rhodium, for instance, can experience extreme price swings – it briefly traded above 20,000 USD per troy ounce between 2020 and 2021, then fell drastically. The high price volatility reflects the tight, geographically concentrated supply structure and the sensitive dependence on the automotive market.
Investors have the following investment vehicles at their disposal: physical bars and coins (for example platinum coins), physically backed ETCs and certificates. The tax treatment differs by metal and jurisdiction; in Ireland, investment gold is VAT-exempt whereas silver, platinum and palladium carry the standard 23 % VAT rate, and private gains are chargeable to Capital Gains Tax at 33 % with no holding-period relief – this is not tax advice. Historical price movements can be tracked under Historical Precious Metal Prices.
Distinction: PGMs vs. other precious metals
Although gold and silver are the best-known precious metals in everyday usage, they are not part of the platinum group. Compared with gold and silver, PGMs are distinguished by even higher melting points, greater hardness and far more pronounced catalytic activity. What all precious metals share is corrosion resistance to air and water and durability against most acids – though PGMs do dissolve in aqua regia.
In a nutshell
Platinum group metals are indispensable industrial raw materials with a highly concentrated supply and price-defining demand from the automotive and technology industries – their scarcity and versatility make them a significant, but price-volatile, segment of the precious metals market.