In 1787, army lieutenant and part-time chemist Carl Axel Arrhenius discovered ytterbite – a strange, unusually heavy black ore found in an old quarry near the Swedish village Ytterby. Ytterbite was later renamed gadolinite.
This unassuming village in the Stockholm archipelago is regarded as the single richest source of elemental discoveries in the world – and is touted as one of the most important places in scientific history.
Eventually as refining techniques improved, in the century that followed Arrhenius’ original discovery 10 elements in total were isolated from this one single ore.
Village streets in Ytterby are named after the many elements discovered there, which include yttrium (Y), terbium (Tb), erbium (Er), and ytterbium (Yb), as well as holmium, gadolinium, scandium, tantalum, and thulium.
All of these elements are rare earth elements, meaning they are very difficult to separate. It took many chemists and scientists decades of research to discover them all.
One of these is gadolinium, which was named after Johan Gadolin. While historical accounts differ, Rareearths.com says in 1880, while investigating the mineral samarskite, Swiss chemist Jean Charles Galissard de Marignac discovered a previously unknown oxide.
Other scientists later confirmed the existence of the new element and named it after Gadolin, who investigated the first known mineral containing rare earths at the end of the 18th century. Pure metallic gadolinium couldn’t be extracted until 1935.
While Sweden is credited with being the birthplace of these important elements, presently China dominates the global rare earths market supply chain.
As Mining.com.au has covered extensively, China’s Ministry of Commerce and General Administration of Customs has implemented export control measures on certain items related to seven types of rare earths. Included in the list is this aforementioned little-known rare earth element called gadolinium, which is used in magnetic resonance imaging (MRI).
Gadolinium rarely makes headlines, but the silvery-white, malleable and ductile metal is poised to see a spike in demand in Australia with the federal government implementing reforms seen as a barrier to accessing it.
Removing barriers
The Australian Government has been removing the final barriers to access MRI services. The reforms include a pathway to expand access to MRI services, improve the viability of nuclear medicine imaging, and a mechanism to ensure sustainability of Commonwealth supported computed tomography (CT) services.
From 1 July 2025, any practice location that holds a current licence will receive a ‘practice-based’ licence that provides full Medicare eligibility to all MRI equipment located at the practice.
Sites without an existing MRI licence will need to wait until the next phase.
From 1 July 2027, all comprehensive diagnostic imaging practices will have their ineligible MRI machines upgraded to access all Medicare funded MRI services, at which point all MRI licensing requirements will cease.
The Australia Government has committed $162.6 million to implement three reforms to Medicare funded diagnostic imaging services, which could lead to more MRI equipment being needed as medical practices ramp up services.
CT expenditure in Australia is growing at a faster rate than most other areas of Medicare, and represents the largest expenditure of any imaging modality, with $1.5 billion in Medicare benefits paid in 2022-23.
Australia has significantly more CT machines per capita than most other countries. The federal government says this is likely attributable to CT having no licensing restrictions.
By reducing fees and helping support patients to access more appropriate imaging modalities, rather than limit access to CT, through reinvesting in MRI and nuclear medicine imaging, gadolinium could soon move out of the shadows as demand ramps up.
According to Inside Radiology, gadolinium contrast media (sometimes called a MRI contrast media, agents or ‘dyes’) are chemical substances used in MRI scans. When injected into the body, gadolinium contrast medium enhances and improves the quality of the MRI images (or pictures). This allows the radiologist to more accurately report on how one’s body is working and whether there is any disease or abnormality present.
Gadolinium contrast medium is used in about 33% of MRI scans to improve the clarity of the images or pictures of a body’s internal structures. Gadolinium contrast media consist of complex molecules, arrangements of atoms held together by chemical bonds.
The chemical bonds are made between a gadolinium ion and a carrier molecule (a chelating agent). A chelating agent prevents the toxicity of gadolinium while maintaining its contrast properties.
Rapid technological advances have resulted in rare earths like gadolinium growing in importance in many domestic, medical, industrial, and strategic applications because of their unique catalytic, metallurgical, nuclear, electrical, magnetic and luminescent properties.
With the Commerce Ministry now imposing more export controls on rare earths, Western nations will need to expedite exploration and increase mine development of rare earths in order to reduce China’s dominance in the sector.
That’s because China produces about 90% of the world’s rare earths – a group of 15 elements of the lanthanide series.
Metals in the lanthanide series are lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb) and lutetium (Lu).
Additionally, yttrium (Y) and scandium (Sc) are often grouped with the lanthanides and referred to as rare earth elements. Geoscience Australia assesses the lanthanides and yttrium together and has produced a separate review of scandium.
Write to Adam Orlando at Mining.com.au
Images: Capital Radiology, iStock & Unsplash
