Showing posts with label metal. Show all posts
Showing posts with label metal. Show all posts

Aluminium Once Cost More Than Gold

The metal that could only be made in large quantities when electricity became widely available was once valued more than gold. Eight per cent of the Earth's crust is made up of mineral aluminium such as potassium aluminium sulfate. This was used in times past for fire-proofing and tanning of leather.

Today, it is in baking powder and aftershave. The refinement into aluminum metal wasn't theorized until the late 19th century. Hans christian Oersted created the first sample of the metal in 1825. It was highly contaminated. Sodium was then used by Henri Saint-Claire Deville to produce more. In 1845 scientists found it to be extremely light in weight. By 1855 small ingots were made and its price skyrocketed. Indeed, Napoleon 111 valued his aluminium cutlery more the the gold alternative.

Electrolysis was the major breakthrough in the production of large quantities of aluminium. Bauxite was identified as the best and plentiful source material. The price fell 80 per cent almost immediately as it became the cheapest metal available. The price fall is notable: $US1,200 a kilo in 1852 to $US1.00 in the 20th century for the same amount.
Science by Ty Buchanan

Asteroids Can Have Magnetic Fields

It has been found that asteroids can have magnetic fields. This was quite a surprise. Planets have magnetic fields due to a moving molten metal core. Mercury has a very strong field. The reason for this is not yet known.

Vesta is a large asteroid with a diameter of 525 kilometer. It was first identified in 1807 by Heinrich Wilheim Olbers. It is the most easily seen asteroid from Earth. Smaller asteroids hit Vesta and some of the debris falls to Earth. The fallen "rocks" can be linked to Vesta because they have the same spectral color match.

Vesta is unusual for an asteroid as it once had a crust, mantle and molten metal core. The orbiting dawn spacecraft/satellite confirms this. It is now frozen and no longer active. A meteor named Alan Hills A81001 composed of Vestan crust fell to Earth in the Arctic. When it was analysed it was found to have a weak magnetic field.  The original crust gained  a magnetic field when it cooled 3.7 billion years ago. An impact a billion years later hit the frozen crust. This melted and refroze some crust which resulted in magnetism being transferred, imprinted, on rock which became the Alan Hills meteor.
. . . . . . . . . . . . . . . . . . . .
Science
TwitThis

Pensioners Hoarding Is a Witch Hunt

I live and spend money in Australia. Rarely do I get a $100 note in change. Indeed, the economy seems to be flooded with $50 bills. Most people carry a wallet full of them. Despite being completely ruined if folded (they keep the crease for ever), the government keeps destroying the old and releasing new $50 notes.

Now, for someone like a former Reserve Bank official to make the absurd claim that pensioners are hoarding their savings in $100 bills in order to keep their pensions, really takes the cake. What fox hole does he live in? It is just as easy to hoard in fifties as it is in one hundreds, particularly when they come brand spanking new from ATM machines.

Peter Mair is so sure he is right that he is writing to Reserve Bank governor Glenn Stevens. He wants pensioner discounted car registrations, council rates and discount phone rentals stopped forthwith. Ask for a pensioner discount on your telephone line rental and you'll get a belly laugh back. It just does not happen. You can put down you have broadband, but Social Security wants to see a copy of the actual account before you to get a few dollars extra from them.

Make it harder to hoard, Mr Mair says.  Print dollar bills again and don't circulate large denomination notes. The result would be people pushing wheel barrow loads of cash around to do their weekly shopping.  It would take a bold Australian government to adopt the "cashless" society system of Singapore. Though Australians use cards for most transactions many still like the idea of cash in their pockets. Peter Mair thinks the feel of cash can be met by leaving metal coins in circulation. If he would just look around the shops he would find people at checkouts trying to dump the heavy pocket loads of valueless coins for notes.
. . . . . . . . . . . . . . . . . .
Science
TwitThis