Recent Posts

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Gemcad Discussions / Re: Fitting a facet design to a piece of rough

« Last post by RoughCreations on Today at 01:07:07 PM »

I was asking andrewbrown about the small stones we see selling from around the world and not having any clue as to how to choose a design...

... or the expectation of having a finished product of what... 50% of the size of the rough being optimistic?

50% yield from a specific piece of rough is generally very optimistic, generally only achievable if your rough has a freakily-good shape or has been pre-formed by the seller (rare) and would therefore command an extra premium in the asking price.
I think a 25 - 33% yield calculated over many cut stones seems to be closer to the average that normal facetors achieve. Carefully choosing a design to match the shape of your rough would get you closer to 33% average, with nice prismatic rough such as tourmaline crystals etc definitely helping in this regard. Highly irregularly-shaped rough with shallow projections usually means closer to the 25% yield, with unexpected inclusions discovered and requiring removal during the cutting process also affecting the final yield. Other factors such as human error while cutting can also combine to reduce the yield for a given stone, and affect your average too.

What kind of product to expect from a 2.5 carat sapphire or garnet... will wait for your experience... thaks.

So, bearing in mind all that, the answer to your question is unfortunately: That depends....
If I was buying a 2.5ct piece of sapphire rough, I would be focussing on nice clean regularly-shaped offerings only, with the aim (hope?) of getting an 0.8ct finished stone.

RC

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Fossicking Locations / Re: Victorian Sapphires

« Last post by swirly on Today at 11:41:45 AM »

there are small sapphires and zircons in reedy crk eldorado not usually of cutting size size there is small cuttable sapphires and zircons near mansfield

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Trip Talk / The Next Big Trip

« Last post by Barry Simiana on Today at 11:36:53 AM »

Six weeks to go for the start of the next big trip. Missed last year due to life and other matters getting in the way. Myself and the young bloke will be wheels up and heading north for 4-5 weeks. First stop Bundaberg and Innes Beach for some volcanic rock and fossilised coral. Next stop Mt Hay. Quick stop at Groper Creek for a fish, then Innisfail and heading west. Big stop at Agate Creek then the real adventure begins. Finally 40 years too late, heading to the Gulf. Young bloke wants a barra as big as him. That's be one hell of a fish. then we turn south. Cloncurry is the target, with day trips to Quamby, Mary Kathleen, Kuridala. Fullerton River and (hopefully) Wee McGregor. We should fill a few buckets (again, I hope). After a stop at Richmond and Hughenden its a tour of the opal fields and home. Biggest trip we've done. Many rocks to find. With  focus on Cloncurry, anyone wishing (willing) to sell or share a copy of Cloncurry Trails, please let me know.
Thanks

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Gemcad Discussions / Re: Fitting a facet design to a piece of rough

« Last post by Alaskan on Today at 05:54:10 AM »

I was asking andrewbrown about the small stones we see selling from around the world and not having any clue as to how to choose a design...

... or the expectation of having a finished product of what... 50% of the size of the rough being optimistic?

What kind of product to expect from a 2.5 carat sapphire or garnet... will wait for your experience... thaks.

5

Fossicking Locations / Re: Victorian Sapphires

« Last post by Bucket on May 16, 2024, 10:01:06 PM »

Many, many years ago, my club used to go to Morrisons regularly, not for sapphires but a very good quality red/brown/yellow and grey chert. I remember it used to polish very well, but couldn't find the area we went now.

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Jewellery Talk / Re: Green tourmaline set in a cast 10Kt yellow gold ring

« Last post by RoughCreations on May 16, 2024, 01:27:37 PM »

Thanks,
It took me many years of practice to be able to make flawed and crude jewellery, lol.

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Jewellery Talk / Re: Green tourmaline set in a cast 10Kt yellow gold ring

« Last post by Faceting Frank on May 16, 2024, 10:45:31 AM »

Looks good RC. I'm sure your daughter will be delighted with it.

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Ask a "Silly" Question / Re: How to figure platform height for the handpiece, while reading diagrams

« Last post by Faceting Frank on May 16, 2024, 10:41:17 AM »

I have a digital scale fitted to my machine, it keeps a very accurate record of the mast height position. It slides up and down the stem it is fitted to, so does not need to be fixed to anything to record its position. Just need it's base fixed to the mast base. It will transform the way you are faceting your stones, because you can keep a record of the platform position to an accuracy of 0.01deg. You can get them on eBay for about $80, in machinery accessories. I think "milling machine measuring equipment" should get you in the right area.

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Jewellery Talk / Green tourmaline set in a cast 10Kt yellow gold ring

« Last post by RoughCreations on May 16, 2024, 10:19:33 AM »

Just showing off a recently completed project of mine, made for my daughter's birthday.

The stone is a green tourmaline, I cut it in the "Shine Bright" facet design by abfacetdesign.
I forgot to weigh the tourmaline before setting, but it is 6.5mm square, loupe clean, a little under 2ct in size with a very thick girdle.
The gold is about 10Kt, it was cast in one piece at size 6. The stone will never fall out!
I went for the aged, handmade look which is my go-to style these days, (“Wabi sabi”) with hammer strokes still visible and small surface 'defects' retained on purpose. The setting was given a hammered look using a rotary hammer bit to produce a bit of texture and glitter effect, rather than the perfect shiny appearance of much of the commercial jewellery available out there.

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Ask a "Silly" Question / Re: How to figure platform height for the handpiece, while reading diagrams

« Last post by Mestrelascas on May 16, 2024, 09:37:24 AM »

 
My faceting machine as promised... Saturday (in class) I'll try to adapt one of the available designs in this forum... I'll keep the faceting arm leveled at the desired angle, while adjusting platform height... Hope it works!

Any help or feedback is appreciated , specially any hand faceters with similar machines ❤️

Thank you once again

Hugo