Driving me NUTS!!!

Found a nice little piece of Labradorite from our recent Hogarth Range collection and set about cutting. The pavilion went in beautifully and the crown was looking good until I started 8000 pre-polish.

7 out of the 8 break facets came up well but the 8th is sending me round the bend Think I have re-cut all 8 about 6 times but still this comes back to haunt me and I'm running out of ideas!

So far I've tried 8000 on copper (my go to) fast, slow, in fact about every speed available, then I tried 14,000 on typemetal, no different, even gone to 50k finish and it just scratches the hell out of this facet, then contaminates the lap and scratches the hell out of everything else. 8.(



Any ideas gang??? Or is this one for the bin!!

Oh noes

Hmm - this stuff is a plagioclase feldspar isn't it? Near identical to the Springsure labradorite if that's the case. The Springsure material contains very thin sheets of a different material distributed along the cleavages which have occasionally given me some trouble, though usually this stuff is pretty trouble-free.

Maybe you could try roughing up the surface of an old CD and using that?

Tricky tricky! If all the others are polishing good but this one isn't its possible its the "grain" of the crystal causing the issue.

Silly question but have you tried polishing in the opposite direction? I've found that helps with complicated minerals.

Thanks for the input guys, just tried something different as I felt I had nothing to loose. Onto the 50k on my split Barium lap and ran it at top speed, slowly but surely it vanished, made a bit of a mess of the girdle meets but without a 10x you'd never see it.

Now for the next row of steps, see how these go. Going to try high speed on the Barium, 8k outer then onto the 50k inner.

Sneaky, yep mate I tried going backwards, actually made it worse, the whole facet was covered in the degradation. Having tried this and seen the facet destroyed is when I went for the high speed, somewhere over 1000+rpm!!

Ya live 'n learn

Well at least you got it fixed :Y: These things are sent to test us.

Well after all the dramas, got her off the dop this morning. Started at 7.55ct and ended up a 10mm stone at 3.1ct. Cut is a very simple step crown with std brilliant pavilion. Think it would work better in a stronger colour, but other than that I'm happy with the result, certainly plenty of bling in sunlight though picture is taken in a light tent.

Very nice Dihusky :Y:

I've always thought it a shame that the Springsure/Hogarth feldspar isn't really worth anything - it cuts a really nice looking stone.

Lefty said:

Very nice Dihusky :Y:

I've always thought it a shame that the Springsure/Hogarth feldspar isn't really worth anything - it cuts a really nice looking stone.

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Not wrong!

Pat Hogen said:

Lefty said:

Very nice Dihusky :Y:

I've always thought it a shame that the Springsure/Hogarth feldspar isn't really worth anything - it cuts a really nice looking stone.

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Not wrong!

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Surprisingly bright!,,

Lefty said:

Very nice Dihusky :Y:

I've always thought it a shame that the Springsure/Hogarth feldspar isn't really worth anything - it cuts a really nice looking stone.

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Yes it is a shame, then again imaging what the properties would look like if it had high value, every man and his dog would be digging them up and half would be trashing the place. More closed gates...

Awsome. Well done. Perseverance pays off.

Very pretty.

Thanks everyone, maybe I'm a glutton for punishment but I seem to constantly push the boundaries.

The stone I'm doing right now is also throwing up challenges, not so much the stone itself, but seeing what I'm doing... 4 meeting facets each side with only one index increment between each, then add in facet line shifts with refraction. 5 second cut then 5 mins trying to work out the result



Ametrine, stone is 8.5mm wide x 15.5mm long currently, so big facets, working on keel meets, damn they're hard to see.

Ooooh i hate close facets!! Angles to close togther are terrible also. Good luck.

Polish the facets in, very lightly, watch out for coffining - just a reminder, not a lesson. :Y:

On very fine and multiple meet-point facets, I use a sharpie to colour the facet. After making a small adjustment, if I touch and look, I can quickly see if I have been too aggressive or need more adjustment by seeing what black has been removed or is still in place.

I chase more of a quarter second cut when getting those meet points perfect. O

Yep, I often use a sharpie to make things easier to see.

The polish isn't the concern, it's getting the damn meets to line up on the keel :awful: :awful: the lines are so fine you can hardly distinguish them. :argh:

Yep, felt tip is a bonus tool not to be ignored.

Pat Hogen said:

Yep, felt tip is a bonus tool not to be ignored.

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Have a couple of them on the bench the whole time :Y: