Tuesday, December 6, 2011


Rhodium coins are very difficult to make but we finally found a way to reliably make them. The metal is hard and fairly brittle making metal forming difficult. In addition to being one of the most expensive metals in the periodic table, the amount of manufacturing time to make the coins results in a high price. First issue is standard thickness, a 1/10 troy ounce variety may be offered in the future.

Rhodium was discovered by William Hyde Wollaston in 1803 in crude platinum ore. Wollaston removed platinum and palladium from the ore to leave a red salt - sodium rhodium chloride [RhCl6]Na3.12H2O from which he extracted rhodium metal. The element name comes from the Greek word 'rhodon', meaning rose. 

Abundance earth's crust: 1 part per billion by weight, 0.1 parts per billion by moles Abundance solar system: 2 parts per billion by weight, 0.02 parts per billion by moles


Wollaston also performed important work in electricity. In 1801, he performed an experiment showing that the electricity from friction was identical to that produced by voltaic piles. During the last years of his life he performed electrical experiments that would pave the way to the eventual design of the electric motor...

His optical work was important as well, where he is remembered for his observations of dark Fraunhofer lines in the solar spectrum (1802) which eventually led to the discovery of the elements in the Sun. He invented the camera lucida (1807), the reflecting goniometer (1809), and the Wollaston prism...

Wollaston used his Bakerian lecture in 1805, On the Force of Percussion, to defend Gottfried Leibniz's principle of vis viva, an early formulation of the conservation of energy...

Wollaston's attempt to demonstrate the presence of glucose in the blood serum of diabetics was unsuccessful due to the limited means of detection available to him.



  1. so..., could a a brotha hook up a rhodium-titanium-vanadium elvish blade of inestimable hardness, lightness, and durability - with the rhodium recovered from the U-235 cores taken from the very pits of Mordor itself.

  2. interesting. When you say "we", do you mean "you"? as in you or you and your posse minted a rhodium coin?

  3. And you thought you was on it and about it casting bronze..., maybe from time-to-time entertaining thoughts about smelting some iron and try'na fold some steel or summin - all the while DD up in here on the low-low running CNC plasma welders and extracting ore from reactor pits and thangs...,

  4. I actually inquired about purchasing a tenth of a kilo of iridium from Heraeus once with the cover story that I was making fantasy weapons. Sadly, minimum order for physical delivery was 10 kilos, and I didn't have a loose quarter million at the time..

    John, these are excerpts from other articles, hit the "source" to see where they are from.

    I do own a tantalum coin but that's another post....

  5. hm. maybe he has himself an industrial strength mass-spectrometer, and is tossing in garbage and building up his elementarium.

    I'm green-eyed with Envy.