Colours In The Steel

Alloys for drawing Colours on Steel: Alloys of various composition are successfully used for drawing colors on steel. To draw to a straw color use 2 parts of lead and 1 part of tin, and melt in an iron ladle. Hold the steel piece to be drawn in the alloy as it melts and it will turn to straw color. This mixture melts at a temperature of about 437°F. For darker yellow use 9 parts of lead to 4 parts of tin, which melts at 458°F. For purple, use 3 parts of lead to 1 part of tin, the melting temperature being 482°F. For violet, use 9 parts of lead to 2 parts of tin, which melts at 494°F. Lead without any alloy will draw steel to a dark blue.

— Henley's Twentieth Century Formulas &c, 80 (1903, revised).

The End of the Age of Metals

Robert Silverberg, famed science fiction author and novelist, has finally let the caterwauling cat out of the bag. In his detailed and thought-provoking piece in Asimov's, he gives a rundown on what metals are running out, why, and when.

For years I've been advocating investing in metals based simply on what every high school chemistry teacher should know: most metals are consumed faster than they are produced, and some are actually pretty rare - even common-sounding ones like lead, tin, zinc and copper. Well, here we go.

Let's begin with the metal prices as of 1998. These are available at the US Geological Survey website, here. Let's take copper for example. Copper is somewhat of a benchmark metal for the economy. The price of copper in 1998 was US$0.7864 per pound; the highest price had been in 1995 with US$1.3833. (1995 was something of a high water mark for metal prices in the 20th century.) Presently, copper is trading for about $3 (or more) a pound. You can't really stockpile it, but demand is high, and copper is used everywhere by everybody for many things. With power industries eating copper by the kilometre, you can bet on a copper nett demand and steady increases in the value of copper mining shares.

But copper has a few advantages that gallium, ruthenium, and many other less critical but more specialist metals don't have. It is easy to find, easy to extract, and we know where most of it is (Chile, with about one-third of world production). More reactive and comparatively rare metals are running out right now; there was little or no use for gallium in the early 20th century, but semiconductors and computer interfaces use a lot of it now. Dr Armin Reller at Augsburg has been giving estimates for such materials; he thinks many of them will be gone between 10 to 30 years from now.

The bad news is that this is old news. By the time the media got hold of it, it was already last year's news. And not many people bothered. Back in 2003, my forecast was that certain heavy metals (zirconium, hafnium; niobium, tantalum; molybdenum, tungsten; rhenium; ruthenium, rhodium, and palladium; osmium, iridium and platinum) should be held in reserve. Do these names look familiar? They would be to former students who have seen me draw Periodic Tables all over their whiteboards in various classrooms.

Maybe that's what a chemical education is useful for, after all!

A Blade For The Fox

I have seen the special 360 people in this particular year of my life, watched them, written stories about them, thought about them sometimes perhaps as a spatial 360°, listened and quietly empathized with them, been stern with them, been kind to them. I will miss them all, every single one, including the ones who don't quite know me, never wanted to know me, will possibly not ever know me – or I them. My last post was about blades. I was thinking about this when I wrote that post...

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"It's all a matter of blueness. You have to get it just right, the way you hold the edge to the flame, watch the colours curl across the metal as it changes. You see, since all things have fire in them, you must see clearly as it responds to flame. Then you will know what sort of blade it can be. People are like that too."

I kept my gaze trained on the fire. The man crouched next to the great hearth blew gently along the grain. Wisps of breath-fog steamed, making twisty patterns on the hot steel. The steel turned over in his grasp; the rough gloves he wore seemed unaffected by the heat.

"There's also the smell of it. A metal sweats when hot: some essence of it rises with the wind of the fire. Some metals smell poisonous, and their stench will make a man ill, spoil his seed and curdle his blood. Some metals smell sweet, or warm—but they may be just as easily poisonous. We choose the woods to be burnt for the flame; we choose them carefully, that their own vapours may mingle with and destroy the evil in the metal."

A bright green smell came into the room. The blade seemed brighter for a brief moment. I peered into the light to see what was happening, but I saw nothing strange.

"And that is the testing of the blank, even before one does anything craftworthy to it. As with a man, the testing by closeness to fire shows much. When you have done it, though, you can begin to think about how to temper the metal. What you quench the hot metal in is very important—some metals will shatter in the quench, some will weaken or be brittle in time to come."

He turned, rising, dark and serious.

"Making a knife is like making a man. Can you do it?"