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polishing
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Author:  j.mcgee_1985 [ Mon Nov 12, 2018 2:15 am ]
Post subject:  polishing

So i just started faceting today, I got tired of waiting for my larger stones and tried a tiny little color change garnet. Anyway I think I may have been mistaken on what I should use to polish. I have an aluminum master lap with diamond paste, it did not seem to work very well. It was only 8k grit so I knew it wouldn't be perfect but it seemed like it should have been better than what it was. I feel like I might be going about this the wrong way though. Is a master lap used for polishing?

Author:  Stephen Challener [ Mon Nov 12, 2018 3:49 am ]
Post subject:  Re: polishing

No, the master lap is just there to give thickness to thin topper laps.
Aluminum is a poor metal for polishing on, just doesn't work very well. 8k is in the prepolish range anyway so you wouldn't expect a great polish anyway.

Author:  j.mcgee_1985 [ Mon Nov 12, 2018 4:18 am ]
Post subject:  Re: polishing

Thank you Stephen. I bought a lot of garnet rough, so I'll be working with that for a while, what type of lap would you recommend/what do you use?

Author:  AlBalmer [ Mon Nov 12, 2018 12:05 pm ]
Post subject:  Re: polishing

You've got a lot to learn. We've all been there :-)
My personal recommendation is to get a metal-bonded 600 grit lap from a supplier like Kingsley North,
https://www.kingsleynorth.com/skshop/pr ... &catID=109
and one of the Gearloose starter kits.
https://gearloose.co/shop/highest-perfo ... arter-kit/
In addition, the cheapest and very important tool is knowledge. Get Tom Herbst's book "Amateur Gemstone Faceting Volume 1: The Essentials", available from Amazon. Volume 2 can come later.

Author:  j.mcgee_1985 [ Mon Nov 12, 2018 3:00 pm ]
Post subject:  Re: polishing

Yes I do! Thank you for the recommendations Al! When I can I'll pick up that starter kit, but for now just the book and metal bonded lap.

Author:  capcuadrate [ Tue Nov 13, 2018 4:16 am ]
Post subject:  Re: polishing

AlBalmer wrote:
You've got a lot to learn. We've all been there :-)
My personal recommendation is to get a metal-bonded 600 grit lap from a supplier like Kingsley North,
https://www.kingsleynorth.com/skshop/pr ... &catID=109
.


Hi Al,
these laps to me look like a 600 grit topper on a steel base lap. Or is there any difference in durability compared to the toppers I use on an aluminium base lap ?

Martin

Author:  AlBalmer [ Tue Nov 13, 2018 12:45 pm ]
Post subject:  Re: polishing

There's a difference in flatness over time, which is more important to me. I havn't used toppers for very long, but I've heard they are shorter lived (but cheaper). You can also get the solid steel laps, of course, which I like even better.

Author:  JCD [ Tue Nov 13, 2018 5:24 pm ]
Post subject:  Re: polishing

I like ultra laps for polishing, but I also use the darkside by Gearloose and a ceramic lap.

Here is a link to Jeff Grahams opinion of Ultra laps https://www.gemsociety.org/article/spectra-ultralap-lap

A nice bonus about ultra laps is they are cheap.

I just put one on my 1200 lap raise the mast a hair and polish to a mirror finish.

Jim

Author:  j.mcgee_1985 [ Wed Nov 14, 2018 2:50 am ]
Post subject:  Re: polishing

I was ordering a couple more dops from graves and saw those, I thought it was worth a shot for 17 dollars so I ordered the multi pack. I also just got my cerium oxide so I'll have to get one of the batt laps too.

Author:  j.mcgee_1985 [ Wed Nov 14, 2018 2:55 am ]
Post subject:  Re: polishing

Off topic, but I just got the first real stone I wanted to cut and it's pretty big 116 cts. I was looking it over for inclusions and saw what looked like a hair-line fracture on what only seems to be the outside but it curves around the stone and back up. I've never seen anything like it and I don't know what to do about it? Any ideas? It's a heat treated zircon.

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Author:  Stephen Challener [ Wed Nov 14, 2018 4:10 am ]
Post subject:  Re: polishing

That's not a zircon unfortunately. (You can't really identify a stone from a picture, but it's sometimes possible to tell what it isn't--the color, form and size all exclude zircon). It looks more like cubic zirconia (in which case it could have been broken off of a much larger chunk, hence these larger fractures).

Author:  j.mcgee_1985 [ Wed Nov 14, 2018 5:12 am ]
Post subject:  Re: polishing

Can't trust anyone these days.. I'll get my money back at least. I really need to pay more attention the fake cert they sent with it says SR for the optic char. :roll: thanks Stephen. Well I guess it will be a good practice piece.

Author:  1bwana1 [ Wed Nov 14, 2018 9:58 am ]
Post subject:  Re: polishing

Post a copy of this "Cert", I love reading some of those. Maybe we should have a special thread for outlandish stone certifications.

Author:  AlBalmer [ Wed Nov 14, 2018 10:33 am ]
Post subject:  Re: polishing

Some years ago, I had a "discussion" with a vendor at Quartzsite who insisted that his CZ was synthetic zircon. I think he actually believed it.

Author:  j.mcgee_1985 [ Wed Nov 14, 2018 3:03 pm ]
Post subject:  Re: polishing

I went back through and reported every one of the stones they had. And these guys are tricky I noticed some of the listings said egl certified earth mined... Which is the name of the company so technically not lying, but misleading for sure. eBay... There was no picture of the certificate on the listing.

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