DR. HANNEMAN'S MINERAL COLLECTION WILL BE AVAILABLE FOR SALE IN THE NEAR FUTURE
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 Post subject: Curved striations flame fusion sapphire
PostPosted: Mon Nov 09, 2020 9:20 am 
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Hello Again!
I'm having som difficulty seeing the curved striations in my flame fusion sapphire. Do I need higher magnification? Picture is taken in about x40. Also, I don't have Methylene iodide, so i have used baby oil. Is it possible with what I've got?


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 Post subject: Re: Curved striations flame fusion sapphire
PostPosted: Mon Nov 09, 2020 12:29 pm 
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I have had better success with lower magnification.
If you can view it immersed between crossed polars, that should help too.


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 Post subject: Re: Curved striations flame fusion sapphire
PostPosted: Tue Nov 10, 2020 8:42 am 
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Barbra Voltaire, FGG wrote:
I have had better success with lower magnification.
If you can view it immersed between crossed polars, that should help too.


Thank you very much! :)

I tried viewing it immersed between crossed polar. But all I can see are interferens colors, lots!
However, if i view it in the light position I see whats in the picture.
This stone is cut with the opic axis almost perpendicular to the table. Does this mean that I should see curved lines (if any are visible) when looking at the side of the stone? Just want to be sure I'm looking i the right place


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 Post subject: Re: Curved striations flame fusion sapphire
PostPosted: Tue Nov 10, 2020 10:07 am 
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In many stones find I do better with just a pinhole for the lower stage light and the upper stage turned off. Try both light field and darkfield for the lower stage. Make sure you try different light levels as well.

Zoom in, go facet by facet turning the stones in many directions for each facet.

When you see curved striations you should confirm that they are not polishing lines by following them across facet junctions.

If you are using diffused light, make sure that the light levels are low. many people use a bright light which masks the striations which can be very low contrast, more of a texture difference rather than a color difference.

The method that works best for a stone depends to a great extent on the type of synthetic, the coarseness, the contrast, and the radius of the striations.

In some colors of sapphire a blue filter helps tremendously. Especially true of yellow and orange/pink stones


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 Post subject: Re: Curved striations flame fusion sapphire
PostPosted: Fri Nov 13, 2020 3:21 am 
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Thank you 1bwana1!
I don't think I'm doing it right, or my equipment is not fit for the task. :|
The only time I see any color is when the stone is immersed, viewed in the polariscope in the light position. And then the lines looks strait to me.


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 Post subject: Re: Curved striations flame fusion sapphire
PostPosted: Fri Nov 13, 2020 1:51 pm 
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Steve (1bwana1), weigh in here.
The lines look a little curved to my eye.

Any bubbles you can find, Lunacar?


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 Post subject: Re: Curved striations flame fusion sapphire
PostPosted: Fri Nov 13, 2020 2:16 pm 
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No, I can't see any bubbles. But that doesn't at all mean that they are not there. :)
I am just trying to see what is there, but I think maybe I need a better microscope.

I can see the filled in crack that resembles a fingerprint, wedge shaped inclusions and 2 "paralell lines" running through the stone (like its been glued). In the picture above they appear as white, when turned 90* they appear black.


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