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Meteorite Strike Creates New Type of Mineral
Ridgelift writes "Chinese researchers have discovered a new mineral created by a meteorite strike. A new form of chromite was discovered in the shock veins formed by the impact of the Suizhou meteorite. 'The shock of the impact created temperatures of about 2000C and pressures like those at 600 kilometres below the Earth.' Researcher Professor Hugh O'Neill says 'This potentially gives us clues to the orbital velocities of two bodies that come together to produce these shock collisions.' Along with the rare find, the researchers who discovered the new mineral get to name it."
I'm really not sure that this is very significant news. This does not appear to be a far reaching discovery, rather I think it "made the papers" because meteorites are cool and exciting, and a new mineral sounds novel.
On the topic of minerals:
Mineral names are always interesting. They often have absolutely no relation to the substance they identify, let alone follow a systematic naming convention. Many minerals have several names, some more accepted than others, some designated long before geology was a science, and most with little reason and only slightly more rhyme. So, since the names don't have to make sense, discoverers have a lot of leeway when naming minerals.
Apparently this got started in the early days of geology before people figured out any chemistry. When someone found a chunk of something, it would get whatever random name seemed good at the time. Unfortunately, after chemistry was discovered, no effort was made to go backward and rename all the old minerals. So mineral names are something of chaos. We have minerals from actinolite, to kaolinite, to rutile, to zircon, and thousands of others that are almost completely meaningless to any well educated person who doesn't already know what they are.
Chemistry, in its early formitive days as a real science, noticed the mess geologists had made of that nomenclature, and wisely decided to systematize chemical names. Of course mineral compositions are covered under the wider blanket of inorganic chemistry, but geologists still don't refer to minerals by systematic chemical names.
Here's a real example of how silly things can get:
One day around 1977 a geologist discovered a new mineral, and thus got to name it. He wanted to honor another geologist who had the last name of Thompson, but discovered to his dismay that there was already a mineral named thompsonite. But not to be deterred from his original intent, and knowing Mr. Thompson's first name was Jim, he dubbed the new mineral jimthompsonite. Which was all well-and-good, but later a monoclinic variation of the mineral was discovered, so it was named (following scant conventions) clinojimthompsonite.
But that doesn't really tell you too much about the mineral. For the record, clinojimthompsonite is a soft amphibole group mineral.
Guidelines for naming a new mineral generally revolve around how easy it is to pronounce, whether it honors someone in the field, and how much like some other mineral name it sounds. Compare this to the process for naming martian craters!
It's really not too weird to discover new minerals, although it's also not exceptionally commonplace; there are a lot of different ways to combine the naturally occurring elements in inorganic crystals at the Earth's range of temperatures and pressures.
Definition of a mineral, with examples:
For the record, a mineral is commonly accepted to be a mineral given all the following:
(Note: these criteria aren't exactly set in stone, but I can't think of anything that's regarded as a mineral that doesn't fit them.)
inorganic
solid
ordered crystal structure
definite chemical composition
naturally occurring
From a practical point of view, if it's a naturally occurring crystal with a unique X-ray diffraction pattern, it shouldn't be too surprising if it's accepted as a new mineral.
A few examples of what aren't minerals:
Obsidian (volcanic glass) can't be a mineral because it doesn't have an ordered crystal structure.
Coal isn't a mineral because, among others, it is organic.
Various formulas of steel aren't minerals because although they're crystalline (microscopically), they are man made.