Crystals

… the most essential part of a living cell — the chromosome fibre — may suitably be called an aperiodic crystal. In physics we have dealt hitherto only with periodic crystals. To a humble physicist’s mind, these are very interesting and complicated objects; they constitute one of the most fascinating and complex material structures by which inanimate nature puzzles his wits. Yet, compared with the aperiodic crystal, they are rather plain and dull. The difference in structure is of the same kind as that between ordinary wallpaper in which the same pattern is repeated again and again in regular periodicity and a masterpiece of embroidery, say a Raphael tapestry, which shows no dull repetition, but an elaborate, coherent, meaningful design traced by the great master.
— Erwin Schrödinger (1887 – 1961), What is Life? Canto Books 1992, 5.

The prism had a single fracture along one of the edges of the base, by which it had been attached to the rest of the group. Instead of placing it in the collection which I was then making, I tried to divide it in other directions, and I succeeded after several trials in extracting its rhomboid nucleus.
— René Just Haüy (1743 – 1822), quoted in E. C. Philips, An Introduction to Crystallography, 35, Oliver and Boyd, 1971.

[Piezo-electricity] Crystals which have one or more axes whose ends are unlike, that is to say, hemihedral crystals with inclined faces, have a special physical property, that they exhibit two electric poles of opposite charge at the ends of these axes, when they undergo a change of temperature: this is the phenomenon known as pyroelectricity. We have found a new way to develop electric polarisation in crystals of this sort, which consists in subjecting them to different pressures along their hemihedral axes.
— Pierre Curie (1859 – 1906) and Jacques Curie (1856 – 1941), Comptes rendus, Vol. 91, 294, 1880.

The molecular structures of the two tartaric acids are asymmetric, and on the other hand, they are rigorously the same, with the sole difference of showing asymmetry in opposite senses. Are the atoms of the right acid grouped on the spirals of a right-handed helix, or placed on the solid angles of an irregular tetrahedron, or disposed according to some particular asymmetric grouping or other? We cannot answer these questions.
— Louis Pasteur (1822 – 1895), writing to a friend in 1851.

Most pieces of metal do not look as though they are made up of small crystals. A polished silver teapot has a radiant sheen, but there are no markings on its surface to show that it is crystalline. Crystals are usually only seen jutting out of the edge of a piece of metal when the metal has been snapped in two. Because of this, many people wrongly believe that the metals are normally quite even and smooth throughout — rather like a very rigid slab of butter — and definitely non-crystalline, and that for some strange reason an internal change could take place making the metal brittle, so that the metal crystallizes, becomes weak and breaks.
— Kogan, Metals and Mankind, London: Purnell and Sons, 1965.

Penrose invented them, or rather discovered them, without any expectation they would be useful. To everybody’s astonishment it turned out that three-dimensional forms of his tiles may underlie a strange new kind of matter. Studying these ‘quasicrystals’ is now one of the most active research areas in crystallography.
— Martin Gardner, foreword to Roger Penrose, The Emperor’s New Mind, Vintage Books, 1990, xvi.

When aluminium, copper and iron are melted together and cooled, they can solidify to form a grain in the shape of a perfect dodecahedron, a geometric solid whose 12 faces are regular pentagons. Although this dodecahedral grain looks like a crystal, it is not. Crystals are composed of identical building blocks called unit cells, each containing precisely the same distribution of atoms and each fitting together with its neighbours in the same way. A dodecahedral grain cannot be constructed from atoms in a unit cell of a single shape whether they be small cubes or even dodecahedrons. The dodecahedral grain is a quasicrystal.
— Peter W. Stephens and Alan I. Goldman, ‘The Structure of Quasicrystals’, Scientific American, April 1991, 24.

Two particular uses of crystals in electronics are favourites with the New Age philosophers as examples of crystals being somehow ‘attuned’ to the universe: crystal radios and quartz watches. (It should be noted here that the crystals are composed of silicon dioxide, and are not the same as the silicon of a silicon chip.) The association between crystals and frequencies (and hence tuning) is quoted as demonstrating that crystals can be used to ‘tune you in’ to energy, like a radio.
— Richard Chirgwin, The Skeptic, vol. 8, No. 3, Spring 1988.

Crystalline matter is matter that possesses a triperiodic structure on the atomic scale. It is characterized by discontinuous vectorial properties that give rise to ‘crystal planes’ [(1) crystal growth (faces); (2) cohesion (cleavage planes); (3) twinning (twin planes); (4) gliding (gliding planes); (5) x-ray, electron, or neutron diffraction (‘reflecting’ planes); all of which are parallel to lattice planes.
— CRC Handbook of Chemistry and Physics, 58th edition, F-98.

The difference between a piece of stone and an atom is that an atom is highly organised, whereas the stone is not. The atom is a pattern, and the molecule is a pattern, and the crystal is a pattern; but the stone, although it is made up of these patterns, is just a mere confusion. It’s only when life appears that you begin to get organisation on a larger scale. Life takes the atoms and molecules and crystals; but, instead of making a mess of them like the stone, it combines them into new and more elaborate patterns of its own.
— Aldous Huxley (1894 – 1963), Time Must Have a Stop. London: Chatto and Windus, 1945, chapter 14.

A crystal lacks rhythm from excess of pattern, while a fog is unrhythmic in that it exhibits a patternless confusion of detail.
— A. N. Whitehead (1861 – 1947), An Introduction to Mathematics. Oxford: OUP, 1948.

May: ‘Oh. Have crystals faults like us?’

Lily: ‘Certainly, May. Their best virtues are shown in fighting their faults. And some have a great many faults; and some are very naughty little crystals indeed.’
— John Ruskin (1819 – 1900) The Ethics of the Dust, Ten Lectures to Little Housewives on the Elements of Crystallisation, 1866.

Crystals have never suffered from the lack of glamour which so long delayed progress in the physics of the solid state. The travelogues of the ancients are liberally sprinkled with mentions of wondrous gems. The classification of crystals was one of the chief occupations of Arab scientists.
— Gregory H. Wannier, ‘The Solid State’, Scientific American Reader (1953), 140.

A crystal of sea-salt, Buffon explained, is a cube made up of other cubes and doubtless the ultimate constituents of salt are also cubes.
— Francois Jacob, The Logic of Life (1973), 76.

But will you hear of another notorious example of folly and madness in these crystals? There are not many years since a dame of Rome, and she none of the richest, who bought one bowl or drinking cup of crystal, and paid 150,000 sesterces for it. As for Nero the Emperor when unhappy news was brought unto him of a great overthrow and a field lost to the danger of his own state and the commonwealth, in the height of his rage and a most furious fit of anger, caught up two crystal drinking cups and pashed them all to pieces: his spite was belike at all the men living in that age, and better means he could not devise to plague and punish them, than to prevent that no man else should drink out of those glasses: and in very truth, a crystal being once broken, cannot by any device whatsoever be reunited and made whole again as before.
— Gaius Plinius Secundus (CE 23 – 79) The Natural History, translated by Philemon Holland, 461.

We have arrived at the notion that a solid is made of atoms or molecules, set out in a regular pattern, vibrating a certain distance in each direction but never leaving the pattern. This pattern may be perfectly regular and go from end to end of the solid, in which case we call it a single crystal. More often the pattern persists for a stretch of a few million atoms and then breaks off and starts again. This is the state of affairs in most solids, which are made up of little crystals arranged higgledy-piggledy but firmly stuck together.
— F. Sherwood Taylor, The World of Science. London: Heinemann, 1950, 39.

The properties of the metals must depend in the first place on the properties of the individual atoms, and in the second place on the atomic arrangement, which is in effect the state of crystallisation.
— Sir William Bragg (1862-1942), Christmas Lecture at the Royal Institution, 1923

I have often been asked: ‘Why are you always showing and talking about models? Other kinds of scientists do not do this.’ The answer is that what the investigator has been seeking all along is simply a structural plan, a map if you will, that shows all the atoms in their relative positions in space. No other branch of science is so completely geographical; a list of spatial coordinates is all that is needed to tell the world what has been discovered … .
— Sir Lawrence Bragg (1890-1971), ‘X-ray crystallography’, Scientific American, July 1968.

Symmetry is tedious and tedium is the very basis of mourning. Despair yawns.
— Victor Hugo (1802 – 1885), Les Misérables, vol II, Bk IV, ch. 1

The precious stone heliotropium, is found in Aethyopia, Africa, and Cyprus: the ground thereof is a deep green in the manner of a leek, but the same is garnished with veins of blood: the reason of the name heliotropium is this, for that if it be thrown into a pail of water, it changeth the rays of the sun by way of reverberation into a bloody colour, especially that which cometh out of Aethyopia: the same being without the water, doth represent the body of the sun, like unto a mirror: and if there be an eclipse of the sun, a man may perceive easily in this stone how the moon goeth under it, and obscureth the light: but most impudent and palpable is the vanity of magicians in their reports of this stone; for they let not to say, that if a man carry it about him, together with the herb heliotropium, and besides mumble certain charms or prayers, he shall go invisible.

How to tell if jewels are genuine: First and foremost … that all stones which be transparent, ought to have their trial in the morning betimes, or at the farthest (if need so require) within four hours after morning light, but in no wise later.

— Gaius Plinius Secundus (23-79) The Natural History, translated by Philemon Holland, pages 468-9. 

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