The Elementals

In Sapphire & Steel, our mysterious agents are referred to in the title sequence as "elements". Unfortunately, half of those mentioned aren't actually elements - they're alloys and compounds. So I generally refer to this panoply of beings as Elementals, rather than Elements. This reflects that their names do appear to reflect their natures, and whether that be because their names were chosen for them, or they were chosen for their names, it is probably profitable to study the properties of those elements, alloys and gemstones after which they are named.

One pattern which appears to be the case is that masculine elementals are metals, and femminine elementals are gemstones (whether precious or semi-precious). However one can easily argue that the sample size we have is too small to be representative, and do whatever you like with the other elementals about which we have no other data than their names. The examples we have are that Steel, Silver and Lead are all men, and Sapphire and Jet are women.

Canonical Elements

These are the "elements" which are mentioned by name in the title sequence, and therefore we know that they actually exist in the series, even though we have met only four of them.

Copper:
A metallic element. Known as a good conductor of heat and electricity.
ElementCu #29
Hardness2.5-3
Crystal systemCubic
Density8.4-8.9
Diamond:
A precious stone, one of the allotropes of carbon. The only precious stone which is valuable in its pure colourless version. However coloured diamonds, known as "fancies" are also valuable.
ElementC #6
Hardness10
Crystal systemCubic
Density3.52
Gold:
A metallic element, one of the the most precious metals, valued since ancient times. Gold does not oxidize (tarnish) and under normal circumstances doesn't react with other elements either.
ElementAu #79
Hardness2.5-3
Crystal systemCubic
Density15.5-19.3
Jet:
Jet is a semi-precious stone, a hard black variety of lignite that takes a brilliant polish. Lignite is otherwise known as brown coal.
Chemistry40-60% Carbon
Lead:
A metallic element. Atomically very stable, used to shield against radiation. Altomic symbol Pb, from Plumbum, because lead weights were used for Plumb lines. Lead is poisonous, though not as insidiously so as Mercury.
ElementPb #82
Mercury:
A metallic element, liquid at room temperature. Poisonous, it is absorbed through the skin. Mercury has the ability to dissolve many metals and to form new liquid or solid alloys. As a liquid which conducts heat well, it is used in thermometers.
ElementHg #80
Density13.6
Solidifies at-38.9 Celcius
Radium:
A radioactive element.
ElementRa #88
Sapphire:
A precious stone. The blue variety of Corundum. (The red variety is known as Ruby.) Traces of iron and titanium oxides cause the blue colour of sapphires. Yellow sapphire is coloured by iron oxide. Synthetic yellow sapphires are coloured by nickel, not iron. Synthetic blue sapphires have no iron, they are usually coloured with Cobolt. "Pink" sapphires are just pale rubies. Corundum is the second-hardest mineral (after Diamond).
ChemistryAluminium Oxide (Al2O3)
Hardness9
Crystal systemRhombohedral
Density3.9-4.1
Silver:
A metallic element.
ElementAg #47
Hardness2.5-3
Crystal systemCubic
Density9.6-12
Melting point962 Celcius
Steel:
An alloy of iron and carbon, with other trace elements.
Chemistrymostly Iron (Fe)

Potential Elements

These elements and minerals are not mentioned in the series, but that doesn't mean that they couldn't be used as new agents in fan fiction. This list is simply to give you some ideas as to their properties so that you can make your characters fitting.

Agate:
Agate forms by the cooling of rock solutions in crevices and cavities in volcanic rocks (said cavities being formed by hot gasses which then escape). Varigated bands are formed by alternating layers of different colours, and the colours depend on other minerals such as haemetite, limonite and chlorites as well as plain ol' quartz. The shape of the layers depends on the shape of the original cavity. Often the hollow doesn't fill all the way up, so the last bit of solution got to cool slowly, and forms quartz crystals (either pure Rock-Crystal or Smoky-Quartz or Amethyst and so on).
ChemistrySilicon dioxide (SiO2)
Hardnessapprox 7
Crystal systemmixture of cryptocrystaline chalcedony, rhombohedral quartz and shapeless opal
Densityvaries
Amethyst:
Purple to violet variety of quartz crystal. The colour is due to iron impurities and radioactive decay. See Rock-Crystal for more information.
Citrine:
Yellow variety of quartz crystal. Its colour is due to the presence of iron trioxide. See Rock-Crystal for more information.
Electrum:
A natural alloy of gold and silver, often found in deposits of pure gold. Its name comes from its pale yellow colour - "electrum" from the Latin, from the Greek "elektron" meaning amber.
Morion:
Black almost non-transparent variety of Smoky-Quartz.
Obsidian:
A volcanic glass, usually black, formed by the rapid cooling of lava. The exact mineral composition varies.
Onyx:
This is a form of Agate which has alternating white and black bands. Even in ancient times, they used to make fake Onyx by dieing porus agate black (the less porus layers would stay white). The oldest method was to soak the stone in warm honey or sugar solution for a few weeks, to allow the sugar to penetrate. Then they would put it in sulphuric acid, and the sugar would react and leave black carbon behind.
Platinum:
The most valuable natural pure metal, though there was a time when it was cheaper than silver, for which it was often mistaken.
ElementPt #78
Hardness4-4.5
Crystal systemCubic
Density14-19 (21 when pure)
Melting point1772 Celcius
Rock-Crystal:
Clear quartz crystal. "Crystal" is from the Greek meaning "ice". Rock crystal remains cold for a long time in warm conditions, because it is a poor conductor of heat. Thus one way of telling Quartz from cut glass is to run the unknown under cold water, as well as something known to be quartz, and see which one warms up fastest afterwards. If the unknown remains cold in the hand, then it's probably quartz, not glass.
ChemistrySilicon dioxide (SiO2)
Hardness7
Crystal systemrhombohedral - pseudohexagonal
Density2.65
Rose-Quartz:
Pink variety of quartz. The colour is due to the presence of manganese oxide and fades when the mineral is heated to 575 Celcius. Prolonged exposure to air also causes the colour to fade. Usually found as lumpen rock rather than separate crystals. See Rock-Crystal for more information on the properties of Quartz.
Ruby:
A precious stone. The red variety of Corundum. The red colour is caused by traces of chromic oxide. Synthetic rubies are often brighter in colour than natural rubies, because there are less impurities - traces of iron oxide tend to dull the colour a bit in natural rubies, wheras synthetic rubies have no iron. Synthetic rubies are often used in lasers.
ChemistryAluminium Oxide (Al2O3)
Hardness9
Crystal systemRhombohedral
Density3.9-4.1
Sardonyx:
A form of Agate which has alternating bands of orange-brown to red-brown, and white. It was named after the ancient city of Sardis, capital of Lydia, which was a centre for trade in the mineral.
Smoky-Quartz:
A smoky-brown to brown-black variety of quartz crystal. Its colour is probably due to silicon ions being released from their positions in the crystal structure due to radioactive decay. See Rock-Crystal for more information.
Tigers-Eyes:
Semi-precious stone, fibrous banded quartz variety caused by the inclusion of fibres of other minerals, particularly crocidolite. Tiger's Eyes are yellow to brown, "Cat's Eyes" are blue-green, and "Falcon's Eyes" are is blue-grey. See Rock-Crystal for more information on the properties of Quartz.

References

  • The Illustrated Encyclopedia of Minerals and Rocks by Dr. J. Kourimsky
  • Collins English Dictionary Third Australian Edition
  • Course notes from GM115, University of Queensland, 1987