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 Post subject: yehuda HPHT diamond tester
PostPosted: Mon Nov 13, 2017 1:57 pm 
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Hi out there. We recently purchased a yehuda HPHT diamond tester. Pretty nifty. Wondering if anyone has insight into how it works. I am thinking phosphorescence. It doesn't detect CVD synthetics, just HPHT.
Thanks.


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 Post subject: Re: yehuda HPHT diamond tester
PostPosted: Mon Nov 13, 2017 4:38 pm 
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Looks impressive.
Alberto, Mikko, what's going on here?


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 Post subject: Re: yehuda HPHT diamond tester
PostPosted: Wed Nov 22, 2017 2:13 pm 
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HPHT boron-doped diamonds are the most common (and cheap) synthetics on the market nowadays. Usually they feature a presistent phosphorescence if exposed to SWUV. the Machine above - very likely, i mean this is what i get from the video but it should be correct - features a SWUV lamp synchronized with the software. Once the stones are inserted in the black box, the SWUV beam excite them. after a while the beam is turned off and a detector identifies the phosphorescing stones. the software will mark their position on the display for the operator.
et voilà.

downsides:

1) not only HPHT boron-doped Synth phosphoresce, even if rare, there are phosphorescent natural diamonds also
2) this feature (and consequently the machine) could be later useless if the production will switch to other dopants
3) its usually not working for CVD synthetics

my 2 c only...

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 Post subject: Re: yehuda HPHT diamond tester
PostPosted: Wed Nov 22, 2017 2:39 pm 
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Quote:
1) not only HPHT boron-doped Synth phosphoresce, even if rare, there are phosphorescent natural diamonds also


Quite right! Remember the curious Natural Diamond we had at Lang Antiques:
viewtopic.php?f=7&t=14759


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 Post subject: Re: yehuda HPHT diamond tester
PostPosted: Wed Nov 22, 2017 2:46 pm 
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yuks, i remember that rare beauty very well!!! :D :D :D

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 Post subject: Re: yehuda HPHT diamond tester
PostPosted: Fri Nov 24, 2017 9:16 am 
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Alberto wrote:
the Machine above - very likely, i mean this is what i get from the video but it should be correct - features a SWUV lamp synchronized with the software. Once the stones are inserted in the black box, the SWUV beam excite them. after a while the beam is turned off and a detector identifies the phosphorescing stones. the software will mark their position on the display for the operator.
et voilà.


Agree!

There are too many devices like this popping in the industry... OGI SYSTEMS and DRC also offering such devices.
The problem with them is the improper description, giving the false confidence that this will solve one's synthetic diamonds problem...


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 Post subject: Re: yehuda HPHT diamond tester
PostPosted: Fri Nov 24, 2017 5:59 pm 
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How cheap are these boron doped synthetics ?
Are they that common ?


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 Post subject: Re: yehuda HPHT diamond tester
PostPosted: Fri Nov 24, 2017 6:27 pm 
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Isi wrote:
How cheap are these boron doped synthetics ?
Are they that common ?


The melee size are extremely cheap and very common. I was approached by a Chinese manufacturer on linkedin who offered me 2-3 mm rough xls of good quality for 28$ per ct.....1000 cts minimum purchase.. ..and it was more than one year ago....

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 Post subject: Re: yehuda HPHT diamond tester
PostPosted: Fri Nov 24, 2017 6:28 pm 
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I guess polished stuff goes around 100-130 $ per ct...

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 Post subject: Re: yehuda HPHT diamond tester
PostPosted: Sat Nov 25, 2017 4:54 pm 
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Alberto wrote:
I guess polished stuff goes around 100-130 $ per ct...


From a short survey among jewelers in Israel, the price for melee stones goes between 150 and 200 USD per carat.
The quality of the goods is very good.


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 Post subject: Re: yehuda HPHT diamond tester
PostPosted: Mon Sep 24, 2018 2:43 pm 
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Hi,

There is a cheap alternative from Gemetrix in Australia:

http://gemetrix.com.au/products.html


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 Post subject: Re: yehuda HPHT diamond tester
PostPosted: Mon Sep 24, 2018 3:21 pm 
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Couldn't one easily make this determination with a LWSW light source with viewing cabinet?


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 Post subject: Re: yehuda HPHT diamond tester
PostPosted: Mon Sep 24, 2018 3:30 pm 
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Yes

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 Post subject: Re: yehuda HPHT diamond tester
PostPosted: Mon Sep 24, 2018 3:37 pm 
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Sidebar.
While I have Alberto's attention.....GemmoFtir™ works only with loose gems? Nothing mounted?

The GemmoFtir™ identifies diamond type, which I find very useful.


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