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 Post subject: why does topaz give slippery feel??
PostPosted: Sat Oct 05, 2013 8:25 am 
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Location: Kuala Lumpur, Malaysia
This is like a stupid question....but I still wanna ask... :lol:

What causes topaz gemstones to have this obvious slippery feel when squeezed in between fingers? It shouldn't be as simple as "good polishing" isn't it :?:

Many thanks in advance.


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 Post subject: Re: why does topaz give slippery feel??
PostPosted: Sat Oct 05, 2013 11:06 am 
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This would be a great question for Dr. Hanneman!

8)


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 Post subject: Re: why does topaz give slippery feel??
PostPosted: Sat Oct 05, 2013 10:55 pm 
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Mayday! Mayday! Dr. Hanneman!


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 Post subject: Re: why does topaz give slippery feel??
PostPosted: Wed Oct 09, 2013 12:44 am 
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Topaz’s feel is a complex function of the surfaces of the stone, one’s fingers, and the moisture or surrounding medium in which the surface was generated. You might look up the process of froth floatation.

One must remember the surface of any gemstone does not have the same properties as the bulk of the stone. When a surface is fractured new surfaces are created which then react with whatever is in contact with them. This all occurs in the first few layers of atoms and doesn’t effect things like S.G. And R.I. etc.

In other words, I don’t know. :D :D


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 Post subject: Re: why does topaz give slippery feel??
PostPosted: Wed Oct 09, 2013 6:50 am 
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i think we should look at this question from a physic and mechanic aspect, i can think of two theories for topaz slippery culprit, :idea:

1- low slip resistance of Topaz could be related to Atomic structure and molecules bonds...

2- a thin layer of vapored liquid water deposit in topaz surface and causes the slipperiness and that is why it can not properly held when in contact with skin... :arrow: (but this theory should be tested in different humidity)

but simple explanation is: God made Topaz Slippery, and we should not question God! :!:

8) :mrgreen:

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 Post subject: Re: why does topaz give slippery feel??
PostPosted: Wed Oct 09, 2013 5:41 pm 
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Secondary question: Is topaz slippery in rough form, or just cut form? 8)

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 Post subject: Re: why does topaz give slippery feel??
PostPosted: Thu Oct 10, 2013 10:35 am 
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Is this a nice topic to investigate in the field of gemological research? any veteran gemologist wanna instigate a study on this ?? :lol: too bad I can only do research in the field of medicine at the moment....


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 Post subject: Re: why does topaz give slippery feel??
PostPosted: Thu Oct 10, 2013 8:05 pm 
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Barbara O. Ellis, GG wrote:
Secondary question: Is topaz slippery in rough form, or just cut form? 8)

I believe that is two questions. Please define "rough form." I can tell you the cleavage plane is slippery.


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 Post subject: Re: why does topaz give slippery feel??
PostPosted: Sat Oct 12, 2013 9:03 pm 
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I think it would be easier to accept the observation that Topaz has a more "slippery" feel than other gem minerals.
It's a complicated synergy of surface energy, surface tension, and other chemical and physical compilations that makes it unique for this observation..

It's a thesis subject for creating things like bonding petroleum products to aggregates to create a better road paving product.

Some things stick together and some things don't.

Did I mention it's complicated? :)


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 Post subject: Re: why does topaz give slippery feel??
PostPosted: Sat Oct 12, 2013 9:06 pm 
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could it be that cheese burger and fries you were eating?


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 Post subject: Re: why does topaz give slippery feel??
PostPosted: Sat Oct 12, 2013 9:19 pm 
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No, the burger and fries were great, but I agree with Dr Bill that cleavage planes are slippery. :)


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 Post subject: Re: why does topaz give slippery feel??
PostPosted: Sat Oct 12, 2013 9:45 pm 
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superhydrophobic perhaps?


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 Post subject: Re: why does topaz give slippery feel??
PostPosted: Sun Oct 13, 2013 2:29 am 
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Bill Hanneman wrote:
Barbara O. Ellis, GG wrote:
Secondary question: Is topaz slippery in rough form, or just cut form? 8)

I believe that is two questions. Please define "rough form." I can tell you the cleavage plane is slippery.
Okay, Dr. Hanneman, I guess I should have seen that coming :P .

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