Cultural Metamiction

The term is synonymous with "cultural rot" but avoids the loaded politics and challenges the reader to hunt the meaning of the term. Once cornered, the quarry yields a new gem, asking only for meaning in terms of change versus status quo.

Crystalline Rot

When Marie Curie coined the term "radioactivity," a competing term--hyperphosphorescence--was thankfully never adopted. Hyperphosphorescence, while descriptively accurate--lacks simplicity.  Metamictization is another concept that needs a simpler term.

Crystals are highly ordered structures. The word "metamictization" refers to internal destruction, usually caused by radioactive uranium or thorium inclusions--their radiation destroys the crystal's integrity in a sort of rotting from within. "Stone cancer" might seem appropriate, but remember that cancer is unchecked growth.

"Crystalline rot" might work as a simpler term than metamictization because it conveys the notion of havoc wreaked from within--like an organized nation's structure.

The Color Of Steel

So the graduations hang on the wall
But they never really helped us at all

No they never taught us what was real

iron and coke

and chromium steel

And we’re waiting here in Allentown

-Billy Joel*

I wrote a bit about American iron and coke back here, but what is chromium steel?  The Germans, who first mass produced it, called it Edelstahl (noble steel)  We're more humble less deferential and just call it stainless steel. A thin layer of shiny chromium oxide protects the underlying chromium/iron alloy. Scratch the metal and another tiny layer of protective chromium oxide forms.

Stainless steel detail from the Chrysler Building.

Actually, the term "stainless steel" is generic and countless species exist. But they all share iron and chromium. Some stainless alloys further include nickel, molybdenum, vanadium, etc., but this post is about chromium, that most colorful of the transition metals.

Van der Krogt writes about the element's discovery and obvious naming:

In 1797 Nicolas-Louis Vauquelin...[was] determined to find the correct composition of crocoite. He boiled pulverized crocoite with two parts potash obtaining a yellow solution. The solution formed a beautiful red precipitate with a mercury salt, and a yellow precipitate with lead. Adding tin muratic turned the solution green. In 1798 he precipitated lead with muratic acid, dried the green solid, then cooked it for half an hour in a charcoal crucible with charcoal dust. Upon cooling he discovered a network or gray, metallic needles weighing one third of the original...Vauquelin named the new element Chromium, because of the many colours of its compounds. The name derives from the Greek χρωμα [chrōma] = colour.

Chromium also gives color to sapphires, rubies and emeralds.

Chrome bumpers, once ubiquitous, were sucked dry by EPA fellatrices.

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*Only one line really bothers me in that Billy Joel pop song: "But they've taken all the coal from the ground." This is emphatically not true.  US steel production is limited by cheap iron ore, not coal supplies. We are the Saudi Arabia of coal.

Diamond Soufflé

Graphite (as graphene)

Isn't it obvious looking at their structures why so many attempts to make synthetic diamonds fall flat and make graphite instead?

This is backed by thermodynamic data so argue only if you dare.

A Girl's Best Friend is the Blue Diamond*

The structure of graphene got me to thinking of that other form of carbon, viz., diamond:

3D movie: link

Why is diamond so tough, so adamant, so opposed to physical change? I think the answer is called "perfect covalency" but not in an electron sharing sense:

The paradox of the diamond is interesting. Its atoms are not arranged in a tight, closest-packing order. They lack the triangulation of sound architecture. In order for its remarkable rigidity to be understood, I assume that the electrons which surround this meager structure supply it with its resistance to deformation. This is one reason why I cannot assume that electron clouds can infiltrate one another like vapors or ghosts. link

Pure diamond is also colorless and transparent, so what gives fancy (colored) diamonds their colors? The answer is not simply: "there must be something blue inside." An impurity is involved, but not the usual colored metal atoms like iron or chromium found inside other gemstones. The impurities in blue and yellow diamonds are carbon's left- and right-hand periodic neighbors--boron and nitrogen--playing little tricks on the lattice electrons.

Take the perfect 3D lattice of carbon atoms pictured above. Now suppose that we could randomly go in and replace every millionth carbon atom with a boron atom without perturbing anything else. What we get is a boron-doped diamond lattice. Because boron has one less electron than carbon, the entire lattice structure of the diamond is riddled with electronic "holes."

Now it just so happens that reddish-orange light has just the right energy match to promote an electron on an adjacent carbon atom into a "hole" next door. That jump in turn creates a new "hole" and so the next neighbor carbon jumps at the chance to fill the new hole and so on and so forth throughout the entire diamond lattice. Really, a blue diamond is rather like a doped silicon p-type semi conductor. In fact, blue diamonds are semi-conductors--albeit rather expensive ones!

Because only reddish-orange light is absorbed, the remaining visible light appears bluish to our eye because the white light lacks its reddish-orange component: remember the color wheel and complimentary colors!

Likewise, water in a white bathtub appears bluish because it absorbs some of the reddish component of the incident white light. That's also why heat lamps are red too--they are more or less tuned to the wavelength (infrared) that water in food absorbs and converts to heat. Microwave ovens are even better at this.

So what makes yellow diamonds? The answer is slightly more complex. If nitrogen atoms, carbon's other nearest neighbor, are doped into the diamond lattice instead of boron, each nitrogen brings an extra electron into the lattice which is easily promoted to the existing conduction band of diamond by violet light--ergo yellow appearing diamonds. Yellow diamond is analogous to an n-type semiconductor. Here's a link explaining in more detail why blue diamonds are blue and why yellow diamonds are yellow: Link.

Meanwhile, here's a very pretty picture of the Hope Diamond:

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*I don't mean "blue diamond-shaped" Viagra either.

Beryllium Is A Sweet Precious Gift

Different variations of beryl, including 1. golden beryl crystal, 2. heliodore. 3. emerald, 4. aquamarine, 5. morganite

The root word of beryllium is old and familiar and lurks beneath the surface of the commonly used word brilliant:

brilliant
1680s, from Fr. brilliant "sparkling, shining" prp. of briller "to shine" (16c.), from It. brillare "sparkle, whirl," perhaps from V.L. *berillare "to shine like a beryl," from berillus "beryl, precious stone," from L. beryllus (see beryl). In reference to diamonds (1680s) it means a flat-topped cut invented 17c. by Venetian cutter Vincenzo Peruzzi.

Beryl and emeralds were known to Pliny the Elder nearly 2000 years ago and he first observed a physical similarity between the two. In the Middle Ages, transparent, colorless beryl was used to make optical lenses, whence the German word Brille which today still means eyeglasses. The invention and manufacture of actual glass spectacles developed in Italy in the 13th century and improvements followed closely with the development of optics.

The minerologist R.-J. Haüy also observed the remarkable similarity between beryl and emerald (hardness and density), and he persuaded the pre-eminent chemist/pharmacist of his time (late 18th century) Louis Vauquelin (of Paris) to analyze the stones to see if they were chemically alike. In 1798, Vauquelin showed that both minerals contained not only alumina and silica as had previously been known, but also a new element, beryllium, which he extracted as the oxide from emerald. Fredrich Wöhler first prepared metallic beryllium by reducing BeCl_2, with potassium metal. Thus the new element beryllium was discovered.

One caveat: until around 1948, beryllium (symbol = Be) was also known as Glucinium (symbol Gl), reportedly because of the sweetish taste of its chloride salts.

WARNING: Beryllium is considered to be highly toxic so do not, repeat do not taste or chew your precious emeralds!