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Post by pauls on Jun 8, 2020 21:34:55 GMT -5
I was of the opinion that it's impossible to polish Jade. That's against all the evidence of my own eyes that it takes a great shine. I couldn't get jade to shine. Two tricks I was shown were to use a lot of pressure, and to use Chrome oxide, it seems to work, usually.
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billdean
starting to spend too much on rocks
Member since April 2020
Posts: 153
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Post by billdean on Jun 9, 2020 0:39:13 GMT -5
OUCH!…..A lot of pressure equals heat. My fingers are blister now. The chrome oxide is order so I am waiting to see on it. But I will keep trying.
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Post by hummingbirdstones on Jun 9, 2020 8:27:48 GMT -5
Put it on a dop stick to polish it. I have always heard that you have to get jade really hot for it to polish. Then there are some pieces of jade that absolutely refuse to polish no matter what you do.
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mgrets
spending too much on rocks
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Post by mgrets on Jun 9, 2020 13:36:19 GMT -5
This came from a book published, I think, in the fifties. Hope it is legible. I have had good results with nephrite jade using only diamond wheels.
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NRG
fully equipped rock polisher
Member since February 2018
Posts: 1,688
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Post by NRG on Jun 14, 2020 18:26:50 GMT -5
Try tin oxide and if that fails use diamonds
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Post by Pat on Jun 14, 2020 21:17:30 GMT -5
Sometimes I get to the point where I admit I really, really like a matte finish!!
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billdean
starting to spend too much on rocks
Member since April 2020
Posts: 153
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Post by billdean on Jun 14, 2020 21:31:31 GMT -5
I agree with you. Sometimes the matte finishes aren't that bad. I keep practicing and trying new things. Sometimes it works and sometimes not. Each piece is different from the one before. Maybe if I was to get a Chinese girl friend, she could teach me the correct way? Nahhhh, then I would have to learn Chinese, and Jade polishing would be easier!
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billdean
starting to spend too much on rocks
Member since April 2020
Posts: 153
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Post by billdean on Jun 14, 2020 21:44:12 GMT -5
Try tin oxide and if that fails use diamonds I have used both but tin oxide has been the best of the two. The real shiny piece of jade was polished using diamond paste.
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NRG
fully equipped rock polisher
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Post by NRG on Jun 15, 2020 17:34:41 GMT -5
Try tin oxide and if that fails use diamonds I have used both but tin oxide has been the best of the two. The real shiny piece of jade was polished using diamond paste. Jade quality also comes into play.
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gemfeller
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Member since June 2011
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Post by gemfeller on Jun 15, 2020 18:44:11 GMT -5
NRG makes a good point: due to its varied felted composition some jades are vary hard if not impossible to polish. I've had better luck sanding it with silicon carbide than with diamond but that's no recommendation: I struggle with both nephrite and jadeite. The following is written by an award-winning jade cuter, Michael Hoover. It describes an unusual technique (to me) that he uses on jade and a variety of other stones.
"I have been cutting and polishing stone for over 50 years now and over the decades I have developed some unique methods to do just about every aspect of cutting and polishing stone. As I write comments about a known but rarely used method I have decided to try and clearly describe how it is done and to "sticky" it for others to use and perhaps pass on. Thus the recent threads I have added to this section.
"If you are already going to a well worn NOVA wheel 1200 grit polish or a NOVA 3,000 grit polish, you are at the 1st polish stage so just get an 8,000 and 14,000 NOVA wheel for the final polish. I cut commercially and use 3,000, 8,000 and 14,000 NOVA wheels for 90%+ of my final polishing but for most people only doing the 8,000 and 14,000 are fine. I occasionally go to my ZAM setup for a final light "dusting" with ZAM if the 14,000 diamond isn't giving a mirror polish and on some stone, usually Jade, I go to the Fabulstre and then ZAM. ZAM is a polish while Fabulstre has some grit in it.
"I do a test polish on EVERY stone I use to determine the best "mix" to get the best polish. Occasionally I find a stone will "cloud" a bit when going to a 14,000 polish and I drop back to 1200 grit sanding and re-polish to the grit the best polish was observed. This is usually discovered in the test polish stage and with some stone, usually a Jade, the best polish is as far down as a worn 1,200 grit or a 3,000 grit NOVA wheel.
"Again for at least 70% of the stone I polish including most Jades and agates - I use "scuff" polishing which is polishing on the 8,000 and 14,000 wheels nearly dry. I do this with very light pressure especially on stones other than Jade which I polish dry on NOVA wheels at times.
"The real trick for "scuff" polishing is getting a VERY nearly dry wheel for the final polish and to develop a feel for the correct drag. The very slightly damp wheel keeps the stone from hydroplaning on the polishing wheels. I put a cloth bandaid (BANDAID brand 1 inch FLEXIBLE FABFIC) on the end of both index fingers and keep a bowl of water next to the wheels. I get the bandaids wet and let them slightly drag on the 8,000 and 14,000 wheels as I am doing the final polish stages. As the bandaids start to get dryer I use less pressure and faster movement of the stone turning it 90 degrees as fast as I can and then turning it a full 180 degrees every few seconds. This will get you a mirror polish.
"If you drop the stone wash it off in the bowl of water as the drag used to scuff polish will often pull the stone from you. As you are using very light pressure the stones do not break as they fall rather than get slammed by the wheel grabbing them. If they are getting "grabbed" and thrown you are using too much pressure, allowing the wheel to get dry, or moving the stone too slowly.
"Now, initially you will ruin some stones as you will burn them or get steam blow outs from too much heat caused by too much pressure or too slow in turning. The stone should never get any warmer than slightly warm if touched to your cheek although Jade can be allowed to get hot but not too hot to be held against your cheek. You must use the damp bandaids to get this to work. In fact I have determined that the best bandaids are (BANDAID brand 1 inch FLEXIBLE FABFIC).
"I first discovered this when polishing Jade and later found it works on most stone. There are some stones that it MUST not be used on:
Copper based stones such as Chrysocolla, Malachite, Shattuckite, Azurite and Gem Silica
Opal
Turquoise
Variscite
NOTES -
1) 1,200 grit NOVA wheels are the most used wheels in my work. I use newer ones to wet sand and nearly worn out ones for final sanding wet and first stage "scuff" polishing. I do this sometimes with one side getting a drip to be wet sanding and the other side pretty much dry to start the "scuff" polish. In fact I have a problem keeping the worn wheels as I totally wear them out. When I get short on the worn 1,200 grit wheels I use 3,000 grit NOVA wheels for the start of the "scuff" polish.
2) Scuff polishing practices only work with broken in 1,200, 3,000, 8,000 and 14,000 grit wheels. It takes about an hour or two of wet polishing to get a wheel properly broken in. Wheels that are not broken in will quickly shred the bandaids so you will know when they are ready for scuff polishing. You can hasten the break in by dressing the wheels with a CLEAN aluminum oxide dressing stick to take off the worst of the "texture bumps" a new wheel has.
* Eastwind Diamond sells a flat lap they refer to as "Diamond Dot Disks". These have a magnetic backing. These disks can be safely used to "grind" most Jade without causing harmonic vibration issues.
* Often I use spit for the very last scuff polishing on Jade! That is kind of my "secret" stage to Jade polishing...."
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billdean
starting to spend too much on rocks
Member since April 2020
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Post by billdean on Jun 15, 2020 18:46:44 GMT -5
Yes it does!
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Post by knave on Jun 15, 2020 19:02:39 GMT -5
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billdean
starting to spend too much on rocks
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Post by billdean on Jun 15, 2020 19:10:58 GMT -5
I have read Michael Hoover's post a few time on another forum. I do not have any nova wheels and don't even know if they make them for a 8" flat lap. I do have the bandaids though. I have been trying some things I have gained from his article. Thank you for posting it.
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Post by rockjunquie on Jun 16, 2020 8:56:21 GMT -5
I have some purple Turkish jade that I recently finished 2 cabs out of. One polished well and easily. The other didn't polish - at all. No matter what I went back and did, it wouldn't polish. But if you look at them closely, you'd see that they have different compositions. One is more loaded with fine white stringers. That stone had massive micro undercutting between the stringers. Eventually, I did get an even matte finish with no orange peel, but it was a challenge. In my experience, some jade polishes easily and some doesn't. But I always use a light touch on the worn nova wheels to avoid the orange peel and then burn them up on the higher polishing grits. (For me, that would be the spin on 8k, 14k, 50k, 100k.)
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dbrealityrocks
fully equipped rock polisher
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Post by dbrealityrocks on Jun 16, 2020 11:52:55 GMT -5
I polish through 14k then use zam in a muslin wheel. From what I've read the heat moves the molecules across the surface giving a great polish
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billdean
starting to spend too much on rocks
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Post by billdean on Jun 16, 2020 20:08:44 GMT -5
This is my third attempt at these 3 jade pieces. Each time they have gotten a little better. I have been taking them back 2 grit sizes and trying again. Still orange peal especially the one on the right which is Washington jade. The one on the left and in the middle are Wyoming jade. I have some silicone carbide wheels coming for my flat lap. I believe they should help create a smoother surface. I am getting to much vibration with my diamond wheels I believe. I am also experimenting with a much lighter touch when polishing them. Still a matte finish but it's getting better and I am learning a lot. These were also polished with Zam and fabuluster.
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gemfeller
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Member since June 2011
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Post by gemfeller on Jun 16, 2020 20:30:02 GMT -5
Do you have any silicon carbide sanding wheels for your flat lap? An old method involves using a well worn 100-grit SC lap to sand jade. You should let it get pretty hot, contrary to Michael Hoover's advice. I've had pretty good luck using that method and going to finer well-worn SC grades as I proceed.
Another method used in Asia is attaching 4/0 flint sandpaper to a disk: flat for flats and sponge-rubber backed for curved cabs. Break it in with a hard stone until it shows a powdery quality on the surface and sand the jade to a pre-polish. Final polishing is done with 9 parts chrome oxide and 1 part aluminum oxide, usually on leather. I haven't tried that method but plan to. No guarantees on either method.
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NRG
fully equipped rock polisher
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Post by NRG on Jun 16, 2020 22:13:16 GMT -5
This is my third attempt at these 3 jade pieces. Each time they have gotten a little better. I have been taking them back 2 grit sizes and trying again. Still orange peal especially the one on the right which is Washington jade. The one on the left and in the middle are Wyoming jade. I have some silicone carbide wheels coming for my flat lap. I believe they should help create a smoother surface. I am getting to much vibration with my diamond wheels I believe. I am also experimenting with a much lighter touch when polishing them. Still a matte finish but it's getting better and I am learning a lot. These were also polished with Zam and fabuluster. Didya spit on them? Lol gemfeller.... Rick you have had my respect for over a decade. That last post is bar none, the finest I have ever seen. (respect X 19) for you sir!
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billdean
starting to spend too much on rocks
Member since April 2020
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Post by billdean on Jun 16, 2020 22:38:42 GMT -5
No spit….I forgot about that. They will be better tomorrow or I will work at it until they are. Thanks gemfeller. I did try this….9 parts chrome oxide and 1 part aluminum oxide with a leather disk. The stone really grab trying it. Probably not enough slurry on the wheel but it was throwing that green crap everywhere, so I stopped. It also seemed to soak into the stone and turned the white crystals a green color. The one in the middle.
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