A beautiful gemmy dodecahedral crystal of orange spessartite garnet (seehttp://tinyurl.com/pflvbgr) hangs between two masses of gleaming white crystals of albite feldspar. Also growing out of the feldspar right next to the garnet is a prism of schorl, the traditional name given to black tourmaline. All these minerals grew together out of the stewing remains of a granite, that cooled slowly enough to form large crystals and concentrated the rare elements necessary that didn’t fit into the standard granitic minerals (eg quartz, feldspar, mica). In this case, manganese combined with aluminium and silica, and boron, sodium and iron in the tourmaline.
The specimen in the photo (4.3 x 2.7 x 2 cm) was mined in the famous pegmatites of San Diego county in California (such as the Pala mine). It was mined in the early 1970’s and is held to be a near perfect example of the region’s production. Many crystals from here were etched at some point in their geological history, or damaged by the strong tectonic forces linked to the Pacific plate, but this one remains intact.
Image credit: Joe Budd/Rob Lavinsky/iRocks.com
What makes fireworks colorful?
It all thanks to the luminescence of metals. When certain metals are heated (over a flame or in a hot explosion) their electrons jump up to a higher energy state. When those electrons fall back down, they emit specific frequencies of light - and each chemical has a unique emission spectrum.
You can see that the most prominent bands in the spectra above match the firework colors. The colors often burn brighter with the addition of an electron donor like Chlorine (Cl).
But the metals alone wouldn’t look like much. They need to be excited. Black powder (mostly nitrates like KNO3) provides oxygen for the rapid reduction of charcoal (C) to create a lot hot expanding gas - the BOOM. That, in turn, provides the energy for luminescence - the AWWWW.
Aluminium has a special role — it emits a bright white light … and makes sparks!
Bismuth occurs naturally and has the atomic number 83.
It’s the most naturally diamagnetic element and has been known about since the 18th century.
It’s very slightly radioactive with a half-life of more than a billion times the age of the Universe.
On this June 27, 1989:
The Canadian Astronomical Society dedicated June 27 as “Canada-France-Hawaii Telescope Day”. It was built by an international partnership of Canada’s National Research Council, France’s Centre national de la recherche scientifique and the University of Hawaii. It was the first large telescope to be placed at the summit of Mauna Kea in Hawaii, considered by many to be the finest site on Earth for observing the universe. The clarity and uniformity of the atmosphere above the location, and the quality of the telescope have contributed to significant advances in the study of quasars, black holes and other areas of research.
(image: By Vadim Kurland (originally posted to Flickr as IMG_2611.jpg) [CC-BY-2.0 (http://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons http://ow.ly/y8Wuw
text from Canada Science and Technology Museum
What do Freud, Maria Abramovi, Beethoven, and you have in common? For one, the need to sleep.
The science of sleep and its glorious effects on creativity, productivity, and sanity gets a lot of press these days. That said, the sleep habits of some of your favorite writers, musicians, and artists may surprise you a little.
The bedtimes and rising times of history’s greatest minds are inventively illustrated in Mason Currey’s Daily Rituals: How Artists Work. The infographic seems to debunk the myth that geniuses stay up through the wee hours working manically, and that you’re more creative when you’re tired—most of these 27 luminaries got a wholesome eight hours a night.
Interesting approach, Balzac.