For me this is the worst part of the migraine. Sure the headache is terribleâ¦but the post period (postdrome)â¦agh! Usually, a 36 to 48 hr period of comeplete listlessness and nausea. I feel like I had a lobotomy and my head is a empty vesselâ¦Nicholsonâs character at the end of One Flew Overâ¦ comes to mind.
Alexandrite, a strongly pleochroic (trichroic) gem, will exhibit emerald green, red and orange-yellow colors depending on viewing direction in partially polarised light. However, its most distinctive property is that it also changes color in artificial (tungsten/halogen) light compared to daylight.tones that show a dramatic color change and strong colors (e.g. red-to-green) are rare and sought-after, but stones that show less distinct colors (e.g. yellowish green changing to brownish yellow) may also be considered alexandrite by gem labs such as the Gemological Institute of America.
One extremely rare color type, the orange-pink corundum, is known as the Padparadscha sapphire. The most valued sapphire color, however, is that deep dark blue that is the well-known September birthstone color. Sapphires are mined all over the world, from Australia, Sri Lanka, Kenya, China, and the United States.