This very nice pink emerald cut has its tone level grade smoothly down the length of the gemstone. The tone gradation, without a hue (color) shift could be caused either by an increase in concentration of manganese in the darker tone areas or the manganese could be in a higher oxidation level. Mn+3 is a much stronger chromophore (coloring agent) than Mn+2. The possibility of a higher oxidation level for manganese would probably be caused by natural radiation. Even without the chemistry this gemstone would make a great ring stone. It weighs 1.51 carats and is clean with great crystal. A flasher all the way around.
Bruce
About Bruce Fry
I was born in Summit, NJ in 1947 and graduated from Summit High School in 1966. I graduated from the Colorado School of Mines in 1970 and after spending another year in graduate school, I left to see the world of Brazil. After spending some more time discovering myself, I ended up working for the Commonwealth of Pennsylvania for 32 years as an Air Quality Engineer in the Department of Environmental Protection. I retired in 2007 and took up faceting gemstones again after a long hiatus that reached back to my twenties. I had started cutting cabochons when I was 13 and bought my first faceting machine when I was 15, but ran out of money and time until I retired.
My great love in gemology is tourmaline and the collection presented here represents my effort to get as much beauty and variety in the colors of tourmaline as I can. I was particularly lucky in being able to get unheated cuprian tourmaline before copper was discovered in gem grade tourmaline from Mozambique.
