Lapidaryforum.net
Let's Rock => Rock Talk => Topic started by: 55fossil on April 14, 2017, 02:36:36 PM
-
I am looking at buying some Concow Jade. I have heard everything from it is great to it is just basalt. Some people said it had green in the black.
For the price I think it would be far better than Basanite for backing. If it really is black and takes a rich polish I do not care if it is jade but would want to know.
Anyone have any helpful information on this stuff, good or bad. thanks, neal
-
https://www.google.com/search?hl=en&site=imghp&tbm=isch&source=hp&biw=1024&bih=715&q=Concow+Jade&oq=Concow+Jade&gs_l=img.12...2674.2674.0.4343.2.2.0.0.0.0.107.107.0j1.1.0....0...1ac.2.64.img..1.0.0.0.4r_p9f4z560
Google knows, is this it. two of the best rock hounds on the net - Google earth & Google images
-
Yep, did the google search and not much real info out there. Figured that was a sign it is not great stuff. The e-bay sale even says jade-like which was really an honest auction. But if it polishes a brilliant black I do not care.. as long as the price is good. People are always looking for a great black material for backing doublets and triplets. thanks
-
agatzied petrified pine, in the 30s was caledl black jet. or black onyx
-
I am not familiar with the Concow but I have had great luck with Basenite. The material I get out of Mojave is awesome and takes a super polish. I am just very careful to look at the rough in the field as the material with little to no specs in it tends to be darker in color and a smoother exterior. I even cab the material. If you want a piece I can find a chunk in the yard and send it to you, no guarantees that it meets your expectations but it works for me. I included some pics of cabs and some doublets using it.
-
Thanks for the offer. I have a little basanite of top quality that I use for special pieces. It also made some incredible cabochons. This offer I have on the jade (?) is too good not to check on. But there is very little info on Concow Blak jade which makes me a bit apprehensive. I will post something next week after my trip to look at it.
thanks, neal
-
I have worked with it and it is certainly Jade like. I think it is probably a near Jade with a high Actinolite component. It is hard to polish as is most Jade. It is not a deep black like Edwards Black.
-
thanks Michael.... If you are anyone else wants any .... I will see what it is like and post pictures. It is suppose to be really cheap and I have a big pile to select from. I have to trade 1/2 rock and 1/2 cash to get the good deal. There is some on e-bay for about $3 a pound I think but it looks a little more like basalt. Dealer seemed honest about what he has and it was black.
more in a few days....
-
How we tell if it's really jade here in wyoming is to check the specific gravity. Jade is very dense and that will give a clear answer.
-
My father, brothers and I mined black concow jade for 20 or so years shipping a lot of it to Taiwan for use as wristwatch backing material.
The jade formed in lenses and was surrounded by lesser quality basalt.
The jade had a ringing sound when tapped with a pick while the basalt did not.
If you are buying concow jade make sure it "rings" and when grinding turns the water a milky color.
I have a copy (pdf) of the testing results from the Gemological Institute of America.
My father sent them a sample identified as "1 opaque greenish black sawn cube measuring approx. 52 x 50 x 48 mm"
They identified the sample as being "Jade, Nephrite".
When my mother passed away the yard contained probably 20-30 tons of black material.
A lot of the material went to people from the Shasta and Paradise Gem clubs (whom I am very thankful to them for all the help).
I'm sure there was some of the good quality stuff present but I'm also sure that there was a lot of basalt.
This stuff is excellent for backing opals.
-
Rockherder:
Boy, you nailed it. The sad thing is many people believe the basalt is still some form of jade. The pieces I viewed were all basalt but were large enough they may have contained some jade. The guy I dealt with was completely honest bout what he had and told me to make my own decision. The real Concow Jade is beautiful. Lucky I have green BC jade I like. thanks for the story, it was interesting to know the history.
-
I have worked with it and it is certainly Jade like. I think it is probably a near Jade with a high Actinolite component. It is hard to polish as is most Jade. It is not a deep black like Edwards Black.
It depends on the piece. The best Concow could actually be blacker than Edwards since it is opaque even when backlit on a razor edge. In contrast Edwards is translucent on a backlit razor's edge thin piece.
-
My father, brothers and I mined black concow jade for 20 or so years shipping a lot of it to Taiwan for use as wristwatch backing material.
The jade formed in lenses and was surrounded by lesser quality basalt.
The jade had a ringing sound when tapped with a pick while the basalt did not.
If you are buying concow jade make sure it "rings" and when grinding turns the water a milky color.
I have a copy (pdf) of the testing results from the Gemological Institute of America.
My father sent them a sample identified as "1 opaque greenish black sawn cube measuring approx. 52 x 50 x 48 mm"
They identified the sample as being "Jade, Nephrite".
When my mother passed away the yard contained probably 20-30 tons of black material.
A lot of the material went to people from the Shasta and Paradise Gem clubs (whom I am very thankful to them for all the help).
I'm sure there was some of the good quality stuff present but I'm also sure that there was a lot of basalt.
This stuff is excellent for backing opals.
That is a very interesting .pdf file but I doubt the GIA would render the same result today since nephrite has been discredited as a distinct mineral.
-
Here is a picture of the saw we used to slice and dice the concow material as well as a pile over against the fence.
Pieces we pulled out and cut ranged from 10-20 #s to as much as 600.
I remember the big piece we used a "come-a-long" and boards to get it in the truck.