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Subject:Bowenite
Posted By: Super Sun, Jun 09, 2013
While I cannot disagree that the two temple lions could indeed be made of "bowenite" but I must caution the overuse of this term by forum members without fully agreeing on or understanding its exact definition.
I know for convenience, very often we would say many Hongshan jade pieces were made of bowenite. Unfortunately, the term "bowenite" cannot be found in many mineralogy text books.
It is quite possibly the term "bowenite" is basically a term used for the state stone in Rhode Island (a state), U.S.A. and was named by James D. Dana in 1850 for George Thomas Bowen [March 19, 1803 Providence, Rhode Island - October 25, 1828 Nashville, Tennessee], chemist and mineralogist and professor at University of Nashville.
According to Encyclopaedia Britannica: "A green serpentine of exceptional hardness of 6, formerly regarded as jade, is known as bowenite, having been named by J.D. Dana after G.T. Bowen. The original bowenite came from Smithfield, Rhode Island, U.S.A. and a similar mineral was described by Gneral C.A. McMahon as occurring in Afghanistan, where it is carved for ornamental purposes in the belief that it is jade."
According to p. 187 of "The Mineralogical Magazine and Journal of the Mineralogical Society , Volume 9", "Notes on Bowenite or Pseudo-jade from Afghanistan, By Major-General C. A. McMahon, F.G.S. [Read May 20th 1890]:
http://books.google.com/books?id=tTM4AAAAMAAJ&pg=PA187&lpg=PA187&dq=when+bowenite+was+named+by+J+D+dana&source=bl&ots=xaCYfuEfyB&sig=g56KPyU9I6jgErwPW1haLAuHrMc&hl=en&sa=X&ei=yY-0UfHPBLCWyAH16YGoBw&ved=0CDcQ6AEwBA#v=onepage&q=when%20bowenite%20was%20named%20by%20J%20D%20dana&f=false
"In 1858 the Smithfield mineral was said by Dr. Bowen to be equal to that of felspar. J.D. Dana put it at 5.5 to 6, E.S. Dana at 5.5, and Smith and Brush at 5. The Afghan mineral has a hardness of 5.
The Sp. G. of the Smithfield bowenite, according to Dr. Bowen varies from 2.59-2.787. I found 2.59 to be the Sp. G. of the Afghan mineral."
Therefore, it may appear that we may call any serpentine that cannot be scratched by metal "bowenite" just for convenience. But what color can it be? Green only? Or also white, yellow, brown or other colors? Is it felspar, antigorite or just a type of serpentine? Can we readily find them in different parts of the world. I have yet been able to find any credible bowenite material for study. It is more difficult to locate than nephrite. I did find some dark green material that looks exactly like nephrite, cannot be scratched but with a much lower S.G. I also found white material that looks almost like Hetian nephrite jade but without its oily luster, cannot be scratched but with a much lower S.G. than nephrite.
If Bowenite cannot be scratched, then does that mean if it can pass the scratch test, then it should be called jade? If not, then must you confirm it with a specific gravity test to see if it is at least 2.90? or 2.86? What happens if it can pass both the scratch test and specific gravity test, then you will have no choice but to label it as "jade"? Unfortunately, some better quality Dushan jade (a feldspar) and lapis lazulite (from Afhanistan) can pass both tests, should we then call them as "jade" or we are going to reserve the narrow definition of jade for nephrite and jadeite only? The funny fact it was not until the middle Qing dynasty, jadeite was not even considered as real jade and the three credible jade material for many Chinese archaic jade carvings include but not limited to Hetian nephrite jade, Dushan jade and Xiyang jade or Xiu Yu (serpentine, bowenite, nephrite, nephrite-serpentine mixture) Therefore, it seems we may need to have a better definition in what we would consider "jade" and simply cannot use material alone to discern antique or archaic jade, or using hardness test or specific gravity test to tell if a piece is real jade. Super
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