⭐ Gemstone & Mineral Show n Tell

Lefty said:

Kingsolomon said:

https://www.prospectingaustralia.com/forum/img/member-images/578/1429950516_image.jpg
I posted this before , this is a Springsure stone , they look good cut . Lefty sent me a couple more . More of a put in collection stone . Perform well though .

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Hey Barney, I just read that labradorite has cleavage in 4 directions. Do the stones need to be oriented to cut them in the same way as topaz?

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Wow ... Lucky i didnt know that when I was cutting them . Would of added more procrastination to a level that is already high indeed.
Probably explains why I had a little trouble with a couple of them . Just be carefull when polishing . If the compound or whatever builds up to create an unwanted scratch , it won't be just a scratch ... Ittl be a gouge , and can even wreck a star facet ( saying ... While your doing a main )
So I'd say if it has that many planes , just dop it and orientate for best recovery . Unless an obvious plane is at table , then 5 de off I guess . But remember , I dont really know much about this whole gem/faceting thing , the more you learn reveals how little you know . That's the fun of it for me really ... Just here for the ride

Barney

A reasonable amount of the Springsure stuff should be like topaz from Mount Gibson I reckon - it's in it's original crystal shape with little or nothing in the way of stream wear so if you have the crystal in it's proper shape, you should be able to determine where the cleavage lies. The Springsure stones are almost invariably blocky in shape.

But what does "cleavage in four directions" mean exactly? Does four directions mean two planes?

My faceting teacher has just gone trapesing the wilds of north west Queensland on a six week fossicking tour (half his luck!) and the other really experienced person at the club hasn't been in for ages. Other club members facet of course but no one there has the experience of these two blokes. So I can't pick their brains at present.

Do you use Ultralaps for polishing at all Barney? I'm using something similar - which is apparently no longer made, an extremely thin blue floppy plastic disc charged with ultrafine cerium oxide - and it's polishing the smokey quartz I'm doing up a treat. In place of loose polishing compound I guess. They are pretty cheap (though have a limited lifespan), I was considering getting some. Dunno how they go on sapphire - maybe they wouldn't work - but I chase amethyst every other weekend (with varying degrees of success) so I'll probably end up faceting a bit of quartz.

The laps you say are '" thin and flimsy" .? Then that's probably something to consider , the only thing with laps is they all have there own problems . Buy solid stuff you don't have to replace all the time , get one of Anthony's polish laps / special alloy . 6" one / split . Update to a bigger system of his later . You won't look back. Just the polish lap won't set you back too much.

KS

it sounds as though Lefty is referring to the Ultra Laps which are still available through Shelleys & also Aussie Sapphire. You can also use mylar drafting film and spray optical grade cerium oxide on it. The Ultra laps are cheap and although they have a limited life they should last long enough to cost out at less than $1.50 per completed stone.

You are right all laps have their own "special ways"/ &/or problems and it is worth trying a few different ones to see what works for your style of cutting.

A full set of Anthony's laps is on my list - I'm especially interested in his sapphire system - just looking for something I can use for little cost almost straight away.

I've been told that quartz sometimes doesn't like to be polished with diamond, the laps I'm referring to are indeed the ones you mention Dug.

I have had little success using cerium as a cabbing polish but the stuff on these plastic polishing films has done a very good job, perhaps it's a better grade of cerium? Perhaps having the polishing compound fixed into a surface rather than as a slurry helps avoid the "aggregation and flow" problem? In any case, it's done a good job polishing quartz. I have been told not to use them on garnet though.

I originally envisaged myself cutting mostly sapphire and zircon but now I can see myself cutting a fair bit of quartz, garnet and topaz as well. Plus anything else of course but I can get my hands on those things easy enough. Ultimately I will need a variety of laps.

Dug out all the old laps of grandad's, they look mostly in good condition and a couple of the copper ones are actually made by VJ from when they were based in Rockhampton, they don't appear to have ever been used.

Ultra laps are perfect for quartz only, not for topaz or sapphires.
I use them as well, the polish is perfect.
My first lap lasted around 10 stones.

Ihate ultralaps,and I believe they have now been discontinued overseas. They round facets and as barney will tell you he is getting excellent results with my special alloy lap on quartz. I would cleanup those copper laps lefty and use some 3000 powder and aniseed oil to apply to the lap as a good pre-polish lap.I use a leather strip to apply the slurry.

No problems using diamond as the final polish on quartz as some suggest? I have diamond powder up to #100 000 here at home.

Clean / sharp facets come of a good polishing lap . And yes 100, 000 is what I do for quartz , though have had succeed with zirconium oxide / cerium as well . They say quartz dosnt polish with diamond . I beg to differ . This Kind of thing annoy old time facetors . So wont say much more . Make up your own mind try...

With a bit of luck I'll be trying it by this evening

They say quartz dosnt polish with diamond . I beg to differ . This Kind of thing annoy old time facetors

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Funny you mention that Barney, a book I have here - must be 40 years old - says that diamond is a lousy polish in general and should be used only as an absolute last resort when every other polishing mediums have failed. I have polished plenty of cabs on a pad charged with #100 000 diamond and they have all taken on a pretty good polish. I thought perhaps what they were talking about must have been some effect of trying to polish a tiny flat facet versus a large smoothly rounded curve.

OMG Is that a sapphire cluster in host rock Varts??

I m not 100% on this one ,gem in host rock,place of birth

any ideas ,?
anyone?

Very interesting looking find there Varts

Lefty said:

They say quartz dosnt polish with diamond . I beg to differ . This Kind of thing annoy old time facetors

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Funny you mention that Barney, a book I have here - must be 40 years old - says that diamond is a lousy polish in general and should be used only as an absolute last resort when every other polishing mediums have failed. I have polished plenty of cabs on a pad charged with #100 000 diamond and they have all taken on a pretty good polish. I thought perhaps what they were talking about must have been some effect of trying to polish a tiny flat facet versus a large smoothly rounded curve.

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Well I finished my first ever faceted stone, a piece of very pale smokey quartz - I know it's not perfect but I was so chuffed that I almost took the day off just so I could sit at home and look at it

I took a few photos but the camera simply can't show what the eye sees as the stone is moved, the brilliant scintillation. The colour is almost more like a zircon than smokey but I know what it is because I found the crystal myself.

There is some rubbish in it because it was only ever going to be a practice stone. I can now see how easy it would have been to cut that little bit out and have a perfectly clean stone.

And no, I can't really see what they mean when they say quartz won't polish with diamond, I polished it with #100 000 diamond and it took on a pretty damn good polish as far as i can see and did so fairly quickly and easily. The only bit I had some trouble with was the table - the thing just did not want to polish and it took some time but eventually I bent it to my will and it came up nicely. All the other facets polished easily.

Just a footnote on polishing on copper laps. After 36 years of faceting I have never really got a good finish with diamond on copper. Its Ok as a pre-polish and in my opinion its not always the person polishing but other factors like the correct lighting. I use 50w halogen with a frosted lense cover to filter the filament glare. have noticed that some peoples cutting over the years looks great under an incandesent globe and crap under a halogen lamp. So have an honest second look to decide for yourself. The other thing is polishing compounds. same apllies.

Had to grab a few gems while the SDC looked on

This weekends spoils a nice 2.5ct black springs saph pics from a few angles