Showing posts tagged geology
Data from ESA’s Mars Express spacecraft shows a natural-color view of Hooke Crater and the icy plains of Argyre Planitia on the red planet. The western half of Hooke Crater (85.7 miles or 138 km wide) appears here.
To the left of the crater, the Argyle Planitia plains are coated with a thin layer of frozen carbon dioxide. Argyre impact basin provides scientists with one of the locations on Mars with a mixture of young and old terrains, as well as deep and surface materials. The image data was obtained on June 8, 2012.
Havasu Falls, Arizona
National Parks: Day One
The Grand Canyon
Did you guys know rubies and sapphires - which are usually seen in jewellery - are actually the same thing?
When I say the ‘same thing’, I mean they are both varieties of the mineral corundum, which forms mainly in metamorphic rocks, but not limited to. They have the same chemical formula, Al2O3, yet come in different colours and are known to the general public as different ‘stones’.
Rubies and sapphires both must have a certain amount of colourisation and hues to be considered a specific kind of that gemstone. Sapphires can also come in other colours than the dark blue most people know.
The reasons for all these different colours and hues is dependant on the amount of elements found within the mineral.
For example, the ruby’s pink-to-red colours are because of the presence of the element chromium.
Sapphires come in a more array of colours - blue, purple, green, yellow, pink, etc - due to different elements being present like copper, iron, and magnesium; just to name a few.
The best part is, these are all impurities. Funny how impurities actually make something even more beautiful, right? As well, we all know the diamond is the hardest gemstone, coming in with a 10.0 on the Mohs scale, but rubies and sapphires come very close with a 9.0.
Oh yeah, and these varieties can be fluorescent too. Just a bonus to add to the pure awesome that is corundum. Next time you see these gemstones set in jewellery, you’ll now know some new facts to tell others!
Photo credit goes to:
Here’s some more yummy geology photos for you guys!
- Anticline in England by Earthwatcher on Flickr
- Geology in Utah from 1993 by Gord McKenna in Flickr
- Folds on beach by Museum of the University of St Andrews on Flickr
- Geology in Spain by Son Of Groucho on Flickr
- Syncline roadcut in Maryland by *nettie* on Flickr
- Anticline in the Bude Formation, England by Earthwatcher on Flickr
- Road cut by eventualbuddha on Flickr