Friends of Jade

As promised but a little late...before writing this i wanted to re-test some items i have been working with, and also subject some others to some of the same unorthodox methods i have been exploring as of late... great thanks to brian who supplied the chemical composition of our mother stone but, if memory serves me, i believe there are a few more stones with the same composition that are not considered true nephrite... what dale had written about some siberian jades "being so called" continued my query into some of the anomalies i had been finding under the microscope, and using an unconventional tool called the presidium gem tester... working mostly with archaic jades, i don't use the specific gravity test so relied upon by others... the reason for this stems from the degradation of the jade material after extended burial, and the fact that many items have been repaired and the old and new glues used also throw the conventional tests off... however, when working with nephrite and the gem tester (which measures resistance to heat and cold, and was originally designed to test diamonds, rubies, quartz, etc.), i have found some interesting things concerning nephrite... as we all know, nephrite is not a good conductor of heat because of its fibrous nature -- however, some nephrites are showing to be much higher in conductivity than others... for example--white to grey nephrite items from the approximate 'warring states era' will peg the machine as high as the finest jadeite, while montana, siberian and polar jades show much less ability to conduct heat... the exception to this rule was found in the more translucent polar jade tree carved by mike burkleo... also, i have found that the higher the reading, the more natural fractures in the nephrite... also, the finest translucent jades from kotan seem to consistently read higher on the machine while the more opaque nephrite shows more resistance... verified under the microscope, the more translucent the nephrite the less fibrous its composition and the greater the occurance of fractures in a genuine archaic item, with the opaque neolithic items bearing out this hypothesis...these more fibrous pieces appear to "shed" the outer skin over time much more hesitantantly, and while this is only a preliminary observation, i believe it might deserve some further study in a more sophisticated setting than my humble work station...in another vein, and knowing well i have little experience with jadeite, i have been finding some obvious anomolies there... first, examining a fresh slab of guatamalan jadite that peter shilling purchased at the last tucson gem and mineral show, i got a chance to look at it under the microscope... the familiar "grainy" pattern was most evident between 20 and 45 power, but when the slab was moved just slightly there apppeared the unmistakable fibrous pattern of nephrite -- within a half-inch, the stone changed, and this occured over the enire surface of the jadeite slab, with most of it grainy but other parts fibrous... also, i have had a marvellous chance to view an enormous amount of older estate pieces of both nephrite and jadeite...taking, as an example, an approximate frame of 80 to 100 year old pieces, the nephrite items were still as polished, while all the jadeite pieces showed signs of surface fractures (like a cracked, dry lake bed)... this i also find on old rubies, sapphires, emeralds, etc., but never on the more opaque nephrite... also, having only one piece of funerial jadeite, it appears it may also degrade at a quicker rate than nephrite, but it could also be affected (as all stones are) by soil composition, moisture, tectonic movement and the like...
i use this thread to continue in the vein that not all is known about what occurs in the depths of mother earth, and try to stimulate some further research from our colleagues... in closing, if there is anyone out there that would like to share a piece of pseudomorph nephrite or a big sur piece for me to examine, it would be appreciated... while i have heard the nephrite replaces the quartz crystals in the pseudomorphs, my suspiction is that it might also incorporate it into its stucture...thank you all for letting me leap over the cliff here...

i've been promoting washington jade for about three years. some of it appears to be exceptionally unique when compared to other jades from around the world. i have a bot formed on top of what looks like jasper, some stones have quartz or agate included, one stone tested had copper, another has beautiful red dendritic moss like inclusions and i have hundreds of bots. anyway, your commentary is very interesting and i suspect there is much to be learned about a metamorphic stone that by definition cannot be just a specific formula or designated recipe. the stones i've had tested were tested in a way that averages the composition of the stone. this is done by testing a large area of the stone rather than a specific minute area that could result in several outcomes after several tests on the same stone. a website, washingtonjade.com, is just getting started and will be displaying some of the stones i have mentioned in the future. thanks for your info.

thanks for the info ken and i look forward to seeing your web site very soon...i agree on the testing of each stone in multiple places as some of mine i have tested over 100 times...it is a sure way to get a feel for the overall stone...for instance i have a cicada that is testing at serpentine on one half and jadeite on the back, white, tranlucent half...now, do i tell a prosective buyer it is serpentite or jadeintine???...smile...i have found it best to educate the buyer so they can see what i see under the microscope and see the readings from my limited little measuring device...also, as you suggest, i do not think either nephrite, or jadeite will be allowed to be "pigeon-holed" into an exact as we are want to do...even in the world of crystals there are annomalies constantly being found in field...

dear fred...always grateful to the grandfather of sound advice...your contact at the gubelin lab would be nice to have and i will call for that info because to have a handheld device that give a clear and meaningful reading of both nephrite and jadeite would seem to me to be a winner for all...however, out of respect for the great artists working in this media, both past and present, i feel inclined to at least mention their marvelous "feel" of the stone...the old ones were supposed to be able to feel the stones in the rivers of khotan by just touching them with their feet and it would be my guess that the don salt's and deborah wilson's, etc. etc., would not feel the great need to have such a device...my guess is that the carvers know the feel of the stone so well as to be on par with the finest machine made...it is a tribute to their sensibilities and such a hoot to watch them as they gather and touch and revere their medium of choice...however, however, growing up in the world of science and the world of art i want it all...smile...i will be in contact with you about the lab...best regards, as always... david

David,
Your observations are fascinating, and your enthusiasm comes through loud and clear. I am new to this site so this probably comes quite late. Have you acquired any Big Sur nephrite to test? If not, I have a piece or two to spare.
Steve

Hi Steve, Post some photos of your Big Sur anomalities for us to see!!! David runs www.antiquitiesplus.com and the forum www.timelessjade.com . There are some great new articles about anomalies and you can easily reach him through timeless as I haven't seen him post here in quite awhile.

Hello all,
I have a question. How likely is it that jade would have quartz filled fissures or have quartz sills or dikes? I started collecting in a "new" area and have encountered suspicious white materials in pieces I would otherwise call jade. In a discussion on Mindat someone siad never...that seems highly unlikely to me, giving the ubiquitious nature of quartz, but I figured I'd bow to your wisdom:-)

~Zeke

Thought i'd update...turns out on the same site there was this gem of info:

""True jade" corresponding to the mineral Jadeite is a sodium-silicate in the pyroxene-group which for geochemical reasons do not go with quartz. "Nephrite" "jade" corresponds to a finely crystalline Actinolite ( a calcium-magnesium-silicate in the amphibole group), and this mineral is commonly found with quartz. "

I guess that answers my question...thanks Fred for the links too...I'll be sure to harasss them when I have another obscure jade question ;-)

~Zeke

meant to add this info too:
"At high pressure, albite is not stable and becomes a mixture of jadeite + quartz."

....and for completeness, here is a link to a slide show of one of the pieces this is in reference to;
http://s790.photobucket.com/albums/yy184/jadadara/FINNEYCREEK/LowerSummer09/GreenTiger/?albumview=slideshow

and here is the link to the Mindat discussion with the first post having pictures of quartz crystals in a Wyoming jade. Enjoy!

~Zeke



~Zeke

http://www.mindat.org/forum.php?read,15,117331,117331#msg-117331