Bi-color emerald cut with a secret

 

Emerald cut with exceptional pointed color separation Bright, flawless, medium large bi-color of reddish brown and pale cream. Unusual color separation indicates old terminus.

I love this gemstone.  It has a lot going for it.  It is well over 5 carats and flawless.  The balance of the two colors in the emerald cut is good and the demarcation between the colors is crisp.  I will concede that the colors are a bit different, but that is the name of the game with many tourmaline I quest for.  And its secret is both visible and interesting, which gives me something to carry on about with tourmaline.  The final plus for me is that I got a good price on this bi-color because the colors are not too “commercial” and it is unique in the collection.

Now what is the secret of this bi-color?  Because the almost colorless part of the bi-color is so clean and the way the bi-color is cut, you can see that the reddish part of the gemstone was the old terminus of the crystal.  At least a few of the old terminus facets clearly slope up toward the table of the emerald cut.   The crystal’s  continuation of growth after some change in its growing conditions at the terminus is not exceptional, (all bi and tri color tourmalines would have to have done it), but the sharpness, clarity and visibility of the transition is what makes this gemstone exceptional.

I would like to take a lot of credit for this well engineered gemstone, but outside of choosing the rough off the inter net and working to get a good color balance, I did not know what I had until I finished the gemstone.  As with many tourmalines, if you really want to see how their colors and their tone levels really are distributed in the finished gemstone, you have to turn the the gemstone over to find its secrets.

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.

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