Silver is widely used in jewellery, has interesting light sensitive abilities and has antimicrobial properties, says Prof Allan Blackman from AUT in ep 78 of Elemental.

Argentina and the Rio de la Plata both take their name from the element silver, whose chemical symbol Ag comes from the Latin argentum.

Silver has always played second fiddle to gold as it is not always found as a pure metal in nature. It is very prone to tarnishing, although that hasn't stopped its use in jewellery, cutlery and coins. Sterling silver is silver alloyed with copper to harden it.

Silver salts used to be widely used in photography and they also have use in transition glass lenses which darken in the sun.

While silver nanoparticles have antimicrobial activity, consuming too much silver for its supposed health benefits is not a good idea; United States political candidate Stan Jones has famously blue skin after many years of consuming home-made colloidal silver. This condition is known as argyria, says Professor Allan Blackman from the Auckland University of Technology, in episode 78 of Elemental.

Go to this episode on rnz.co.nz for more details

Silicon is a blockbuster metalloid with many uses, from glass to computer chips & bathroom sealants, says Prof Allan Blackman from AUT in ep 77 of Elemental.

Silicon underpins modern technology and has been a ubiquitous part of our lives since the 1950s, when the silicon chip was invented.

But although billions of silicon chips are produced each year, this only uses 5 percent of the world's silicon production. The rest is used in glass, concrete, brick and silicone polymers.

In nature the most abundant compounds of silicon are feldspars, which are aluminosilicate materials, and quartz or silica, better known as sand.

In episode 77 of Elemental, Professor Allan Blackman from the Auckland University of Technology, introduces us silicates, silicones, silicas and many other permutations and uses of silicon.

Go to this episode on rnz.co.nz for more details

New Zealand soils lack the vital element selenium, which also used to be important in photocopiers and bathroom plumbing, says Prof Allan Blackman from AUT in ep 76 of Elemental.

Selenium is named after the moon. There is some debate as to whether it is a metalloid or a non-metal.

It is a trace element that New Zealand soils are deficient in. As a result, Kiwis are recommended to eat foods such as brazil nuts and seafood that are rich in selenium.

Selenium occurs as three allotropes, and the grey allotrope has the unusual property of being an insulator in the dark but conducting electricity when it is exposed to light. This led to its extensive use in photocopies during the 1970s and 1980s, says Professor Allan Blackman from the Auckland University of Technology, in episode 76 of Elemental.

Go to this episode on rnz.co.nz for more details

Predicted by Mendeleev & useful for alloying with aluminium, scandium was involved in a famous cricket scandal, says AUT's Allan Blackman in ep 75 of Elemental.

Scandium is named after Scandinavia, and it was the second of Mendeleev's predicted elements to be discovered.

Scandium is the first transition metal on the periodic table. It is roughly the same density as aluminium but has a higher melting point, which means it can be welded.

The most famous story involving scandium concerns a cricket bat wielded by Dennis Lillee in a cricket test against England in 1979. The scandalised cricket authorities subsequently amended the Laws of Cricket to state that the blade of the bat must be made of wood, says Professor Allan Blackman from the Auckland University of Technology, in episode 75 of Elemental.

Go to this episode on rnz.co.nz for more details

Samarium magnets are used in headphones & guitar pickups, and samarium was the first element named after a real person, says Prof Allan Blackman from AUT in ep 74 of Elemental.

Samarium was the first element on the periodic table to be named after a real, as opposed to a mythical, person.

It is a lanthanoid and alloys of it are useful in magnets, which can be thousands of times stronger than iron magnets.

These magnets are found in headphones and high-end magnetic pickups for electric guitars and basses.

Samarium magnets were also used in the motors of one of the earliest solar-powered electric aircraft, the Solar Challenger, says Professor Allan Blackman from the Auckland University of Technology, in episode 74 of Elemental.

Go to this episode on rnz.co.nz for more details

Ruthenium is a 'sort of' precious metal that is a useful catalyst and alloy. It is toxic and smells like ozone, says Allan Blackman from AUT in ep 73 of Elemental.

Ruthenium is a rare transition metal produced mostly as a by-product of nickel mining.

It is not widely used industrially, although it is found in some catalysts and alloys. It is more useful in the chemistry laboratory, where it has helped several chemists win Nobel Prizes.

Ruthenium is toxic and if you have the bad fortune to be exposed to it, it smells of ozone says Professor Allan Blackman from the Auckland University of Technology, in episode 73 of Elemental.

Go to this episode on rnz.co.nz for more details

Rubidium is a reactive metal with few uses, named 'deepest red' due to its beautiful red spectral lines, says Allan Blackman from AUT in ep 72 of Elemental.

Rubidium is named after the Latin word rubidius, meaning 'deepest red.'

It is a group one metal, which makes it soft, highly reactive with water and with a low melting point.

Rubidium helped win a Nobel Prize in Physics in 2001 for the discoverers of Bose-Einstein condensates, says Professor Allan Blackman from the Auckland University of Technology, in episode 72 of Elemental.

Go to this episode on rnz.co.nz for more details

Rhodium is an expensive precious metal that is used in catalytic convertors, to make the Parkinson's drug L-DOPA, create shiny jewellery and add the menthol taste to toothpaste, says Allan Blackman from AUT in ep 71 of Elemental.

Rhodium is a very expensive precious metal, whose major use is in catalytic convertors, as it is very good at reducing levels of nitrogen oxides.

The metal is used in mirrors and optical fibres, and as it is very shiny it is sometimes used as a coating for jewellery made from cheaper metals.

Rhodium turns up in lip balm, cough remedies, toothpaste and aftershave, because rhodium catalysts are used to make synthetic menthol flavours, says Professor Allan Blackman from the Auckland University of Technology, in episode 71 of Elemental.

Go to this episode on rnz.co.nz for more details

Named after the Rhine river, rhenium is a metal with very high boiling and melting points, and it was the last naturally occuring, non-radioactive element to be discovered, says Prof Allan Blackman in ep 70 of Elemental.

The chemical element rhenium is named after the Rhine River.

It is one of the rarest elements in the earth's crust and the last of the naturally-occurring non-radioactive elements to be discovered.

Rhenium has a number of claims to chemical fame: the metal has the highest boiling point (5596 degrees Celsius), third highest melting point and is the fourth most dense of all the elements.

It finds use in alloys and catalysts, says Professor Allan Blackman from AUT, in episode 70 of Elemental.

Go to this episode on rnz.co.nz for more details

The radioactive gas radon can be a risk in the basements of stone houses and used to, erroneously, be touted for its health benefits, says Prof Allan Blackman from AUT in ep 69 of Elemental.

Radon was originally named 'radium emanation' by its discoverer, Kiwi chemist Lord Ernest Rutherford.

It is a noble gas and is produced by the radioactive decay of uranium and thorium. People who live in stone buildings can be at risk from radon gas as it escapes from rocks - it is heavy so it tends to lodge in the basements of houses. This is a problem in some parts of the United States, where you can buy radon detectors in supermarkets, but is not an issue in New Zealand.

In the early twentieth century radon was touted as having health benefits before the dangers of radioactivity were recognised, says Professor Allan Blackman from the Auckland University of Technology in episode 69 of Elemental.

Go to this episode on rnz.co.nz for more details