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Interesting comments!

Posted By: Bill
Posted Date: Jun 06, 2010 (08:37 AM)

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Hi, John:

Please forgive me for asking:

If you are from Mayanmar and your family happen to be gem dealers, you know quite well on corumdum (corundum) and lepis (lapis) and you are 100% sure this is blue corundum, then what exactly is the purpose of your posting this piece here for others' opinions?

First of all, what you said about lapis and sapphire (blue corundum) is quite correct:

"SG and hardness of that two stones are quite different."

Sapphire has a MOH hardness of 9 and a S.G. of 3.9-4.1 while lapis has a hardness of 5-5.5 and a S.G. of 2.7-2.9 (I actually see much lower on poor quality of lapis. Many of these so called lapis carvings sold currently are actually made of sodalite which has a hardness of 5.5-6.0 but a much lower S.G. of 2.27-2.33.

Therefore if you would be kind enough to post the S.G. and MOH hardness of your "Blue Corundum" piece here, then their test results will speak for itself since you did say "The SG of our blue sapphire vase can be measured very easily by using mechanical balance."

Now if you would say you had not tested your vase yet, then I wonder how you could have said "I am 100% sure this is blue corundum."

Also, I am also quite puzzled with your statement:
"Since old times, my people have no skills in curving corundum as it is too hard. Only Chinese knew how to curve it, so it is our main curiosity. "

I am very curious to learn from you where you got the idea that Chinese knew how to "carve" corundum which has a hardness of 9 since old times? What exactly are OLD TIMES and how in the world the Chinese could have carved a "corundum" piece as large as yours with a hardness of 9? With diamonds? There was simply no record of diamond was being used in carving any large corundum carvings in China at old time or even modern time. Even with all the modern tools today, it would be hard-pressed for any carvers to carve such blue corundum vase.

Secondly, where in the world one would find such a large piece of blue corundum and why would one used it to carve such an ugly vase (forgive my saying so).

You also said "Greatwarrior Gangis (Genghis) Khan had blue sapphire curving weared (worn) on his arm. That blue sapphire was of Burmese origin. It was exhibited in Burma in 1967,"

I would be glad if you would be kind enough to give me some references for this story.

At first I also thought that this might be made of sodalite, however when I look at its bottom, its texture dose look a little bit like a piece of red corundum I have. Therefore without further testing results of your vase, it will be unfair for any of us to continue in guessing what material was used to made your vase. Therefore, if you would be kind enough to share the S.G. and MOH hardness of your vase with us, I believe it would be very helpful. Thanks.

Bill

(Bill without the H)

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