Osmium - the Eighth Precious Metal: A Comprehensive Review of the Rare PGM

A new review paper provides one of the most comprehensive overviews to date of osmium, the least-produced and arguably least-understood member of the platinum group metals (PGMs).

Authored by experts from TANAKA Precious Metals, Auris Noble and Metalor Technologies, the paper explores osmium’s unique position within the precious metals family, covering its history, market structure, production, chemistry, applications and future prospects.

Despite being recognized as a precious metal since its discovery in 1803, osmium has historically occupied a niche position due to its extremely low production volumes, challenging metallurgy and the formation of osmium tetroxide (OsO₄), a highly toxic but industrially valuable compound. The review highlights a significant milestone achieved in 2025, when ISO formally included osmium within its definition of precious metals, alongside gold, silver and the other PGMs.

The paper estimates current global osmium demand at approximately 1.5 tonnes per year, making it the smallest precious metals market by volume. Most supply originates as a by-product of platinum, palladium and nickel production, with South Africa accounting for the majority of primary supply.

Beyond its distinction as the densest stable element, osmium plays a critical role in several highly specialized applications. These include catalytic processes used in organic synthesis, transmission electron microscopy, advanced materials science and emerging areas of medicinal chemistry. The authors also examine recent developments in jewellery, investment products and crystalline osmium, while providing a balanced assessment of market opportunities and challenges.

As interest grows in niche precious metals and advanced PGM applications, this review offers valuable insight into a metal that remains small in volume but significant in scientific and technological importance.

Read the full paper to discover why osmium is increasingly being recognized as the eighth precious metal.

Head to our Six Metals section to download more fact sheets on each of the six platinum group metals.