Thursday, 14 May 2009


This week a South African blue diamond was sold at auction in Geneva for £6.2 million after a bit of a bidding war. This makes it the most expensive blue diamond ever. It's set in a platinum ring, and doesn't look very big. If I was spending that much, I'd probably want something a little bigger. Car-sized, maybe, or at least the size of an overweight cow. The diamond will be named by its new owner. Unlike Cabbage Patch dolls, they don't come with a wee label with their name, hobbies, etc. What will it be called? Is it like a show dog or racehorse where they have their 'stage' name, like Fragrant Broccoli Starfield for example, and then their 'pet' name, such as Stumpy? I don't know the answer to this.

Diamonds, in their purest form, are colourless. They are pure carbon. The presence of trace elements during formation, radiation and also slight physical deformations can influence the colour, though, and diamonds can be found in a number of colours. After clear, the most commonly found are brown and yellow, where Nitrogen is present. Red, pink, orange, violet, green, purple, blue and black varieties are also found. Black diamonds are usually the result of inclusions of graphite, the 'lead' in a pencil and another form of pure carbon, but as soft as diamond is hard. Blue diamonds are formed when there is boron present.

Diamonds form when carbon-rich rocks are subjected to high pressures at (geologically speaking) relatively low temperatures. While almost all are formed deep under areas of the Earth's continental plates (not oceanic), very small diamonds can be formed on meteorite impact. It's no use squeezing a lump of coal to form a diamond. That doesn't work. Even after 37 minutes. I got bored.

No comments: