January 24 Through February 4—TUCSON, ARIZONA: Annual show
Welcome to the GemologyOnline.com Forum
A non-profit Forum for the exchange of gemological ideas
It is currently Thu Mar 28, 2024 9:50 pm

All times are UTC - 4 hours




Post new topic Reply to topic  [ 50 posts ]  Go to page Previous  1, 2, 3, 4  Next
Author Message
 Post subject: Re: Violet Blue Stone Diamond OR Dud
PostPosted: Sun Dec 05, 2010 11:18 am 
chevalier wrote:
Look, I am an absolute novice (at least to quantitative/determinative gem testing and identification, not necessarily of gemlore and their use in jewlery), but it seems to me that one can't trust solely on'es instruments: one collects as much data as possible from a variety of sources (instruments, physical properties, visual observation), rules out as much as possible, and then uses seasoned judgment to determine which gem species and variety it is, and how it grades or values.

C.


OK, if it suits you, you do that and no harm done; it's your money. Now try and sell what you have bought to a professional, on no more that the basis of what you think and feel about it....

Sell to an 'Average Joe' customer who then seeks a professional appraisal of what he bought on your assurances and finds that he has not got the finely cut natural ruby you promised but a finely cut synthetic..... and guess what will happen next :roll:

Point made?


Top
  
Reply with quote  
 Post subject: Re: Violet Blue Stone Diamond OR Dud
PostPosted: Sun Dec 05, 2010 2:55 pm 
Offline
Site Admin
User avatar

Joined: Sun Oct 16, 2005 12:22 pm
Posts: 21602
Location: San Francisco
chevalier wrote:
Look, I am an absolute novice (at least to quantitative/determinative gem testing and identification, not necessarily of gemlore and their use in jewlery), but it seems to me that one can't trust solely on'es instruments: one collects as much data as possible from a variety of sources (instruments, physical properties, visual observation), rules out as much as possible, and then uses seasoned judgment to determine which gem species and variety it is, and how it grades or values.

C.


This is an absurd argument.

"I am an absolute novice to gem testing, therefore I base my opinions on seasoned judgment." #-o Did you ever consider your judgment might be based on bad information, misunderstandings, misrepresentations and misinterpretations. (Not to mention ignorance and arrogance.)

Of course one can trust their instruments if they invest in quality tools and know how to use them and learn to interpret results.

Well I hope you are only a consumer.


Top
 Profile  
Reply with quote  
 Post subject: Re: Violet Blue Stone Diamond OR Dud
PostPosted: Sun Dec 05, 2010 3:23 pm 
Offline
Valued Contributor
User avatar

Joined: Wed Oct 20, 2010 4:20 pm
Posts: 139
Location: Australia
If this is the state of our consumers, no wonder synthetics flourish.


Top
 Profile  
Reply with quote  
 Post subject: Re: Violet Blue Stone Diamond OR Dud
PostPosted: Sun Dec 05, 2010 3:59 pm 
Offline
Gold Member
User avatar

Joined: Wed Nov 15, 2006 9:44 pm
Posts: 1079
Location: Washington State
chevalier wrote:
it seems to me that one can't trust solely on'es instruments: one collects as much data as possible from a variety of sources (instruments, physical properties, visual observation), rules out as much as possible, and then uses seasoned judgment to determine which gem species and variety it is, and how it grades or values.


But one's instruments are all that one has to gather the data used in making a determination. Of course, a person has to know how their instruments work and be able to understand if the data they are giving is potentially inaccurate, (if the measurement given seems to be incorrect, then a person needs to be able to see this and understand what may be happening to give an errant reading, then fix it or use other instruments to give a better understanding).

The use of a thermal tester is a good case in point. They are designed to heat the tip of the instrument and then measure how much heat is removed when they are touched to an unknown sample. If that sample is dirty, wet, sharply curved, internally fractured or fracture filled or has some other features which are not consistent with the samples used to calibrate the instrument, then you may get a reading which could be far from accurate. If you don't understand this and use other instruments for further testing, then you can be easily misled into thinking that a sample which has a vanishingly small chance of being a diamond, is a diamond, (potentially very embarrassing).

_________________
Michael E.


Top
 Profile  
Reply with quote  
 Post subject: Re: Violet Blue Stone Diamond OR Dud
PostPosted: Sun Dec 05, 2010 4:56 pm 
esjayp wrote:
If this is the state of our consumers, no wonder synthetics flourish.


If you really want to make money, put you money into a synthetics development company and not some hole in the ground. The stuff is frequently developed in secrecy with big govt bucks behind it and the gem market usually does not get a sniff of it until it has become a global commonplace and therefore no longer subject to strategic controls.

Cases in point are YAG, CZ (decades ago) and even Quartz (maybe more than half a century ago). There are others, some of which no doubt the gem trade has yet to get to play with.

As we see here from time to time, the beuuty of a finished gem is much to do with the lapidarist and jeweller's skills and little to do with whether the stone is synthetic or real. Sooner or later, I think the gem market must adjust to this reality. Historic and even high-end antique stuff may hold its price but, outside of those two narrow fields, if I were to invest in finished gems, it would be in the output of the very best cutters and without any premium for whether or not a stone was mined and without regard to whether the stones were treated or left untreated. These differentials in price which still hold for the time being are, I think, treading on cracking ice ever more reluctannt to bear their weight.

Just my 2 cents


Top
  
Reply with quote  
 Post subject: Re: Violet Blue Stone Diamond OR Dud
PostPosted: Sun Dec 05, 2010 6:24 pm 
Offline
Platinum Member

Joined: Tue Nov 29, 2005 2:02 pm
Posts: 2646
Back to the original post; can someone show me an example of a cabochon cut diamond? Then explain how the cutter dealt with the directional differences of hardness to achieve the cut.

Of course it's not a diamond. Of course the OP needs a professional evaluation.


Top
 Profile  
Reply with quote  
 Post subject: Re: Violet Blue Stone Diamond OR Dud
PostPosted: Sun Dec 05, 2010 6:46 pm 
Offline
Established Member

Joined: Tue Nov 16, 2010 1:47 pm
Posts: 46
I don't think anyone understand what I was saying--either I was misinterpreted or I phrased things incorrectly (or both). If anything I was expecting someone to say "well, duh!"; I thought I was saying something obvious!

1) "This is an absurd argument. 'I am an absolute novice to gem testing, therefore I base my opinions on seasoned judgment' ".

Barbra, you absolutely misquote! I deliberately used "one". Not "I". I meant a professional, one who has seasoned judgment, (or I guess at least wants to in the future!)

What I meant was: if one is looking at a purple cabochon cut gem, (I say one b/c I don't mean "you" in paricular) and for some reason one applies a gem tester, and it reads diamond, well common sense and good judgment should override (word choice?) that instrument. Or one should take other data from other devices, and count the totality of the data (including the visual clues) to make one's decision.

Also, "ignorance and arrogance"?

2) Kerensky: Please re-read my post. You will kindly see I say "one collects as much data as possible from a variety of sources (instruments, physical properties, visual observation)" (ie does modern scientific derminative gemology) and nowhere do I use the word "think and feel". You state the opposite of what I suggest, it appears.

3) Michael E. "But one's instruments are all that one has to gather the data used in making a determination. Of course, a person has to know how their instruments work and be able to understand if the data they are giving is potentially inaccurate, (if the measurement given seems to be incorrect, then a person needs to be able to see this and understand what may be happening to give an errant reading, then fix it or use other instruments to give a better understanding)."

Yes, yes! Absolutely. This agrees with what I am saying. (Well, one's scientific instruments and natural senses.)

Let me rephrase my original post, please and see if it sits better.

"Hey, I'm new to this, but it seems that they way it works you can't just trust one instrument, or even a few readings. You have to compare a lot of data of different sorts to known facts to make a gem identification, and not just one reading. And if one of your readings is leading you to a conclusion that seems improbable or against factual data, you should use the totality of the evidence collected to make your determination. And to the last bit I add, including checking your instrument, retaking your measurement, etc.

IE: don't use one electronic diamond tester and call it a day.

Regards,

C.


Last edited by chevalier on Sun Dec 05, 2010 6:54 pm, edited 1 time in total.

Top
 Profile  
Reply with quote  
 Post subject: Re: Violet Blue Stone Diamond OR Dud
PostPosted: Sun Dec 05, 2010 6:52 pm 
Offline
Site Admin
User avatar

Joined: Sun Oct 16, 2005 12:22 pm
Posts: 21602
Location: San Francisco
My apologies. I totally misunderstood what you meant.
And, as it turns out, I think we are making exactly the same point.


Top
 Profile  
Reply with quote  
 Post subject: Re: Violet Blue Stone Diamond OR Dud
PostPosted: Sun Dec 05, 2010 6:57 pm 
Offline
Established Member

Joined: Tue Nov 16, 2010 1:47 pm
Posts: 46
Barbra Voltaire wrote:
My apologies. I totally misunderstood what you meant.
And, as it turns out, I think we are making exactly the same point.


Barbra, thank you, and I think we are too! I learned a lot of the point I was making (collect solid data and use good judgment) from your many helpful posts to novices such as I on this board/forum.

C.


Top
 Profile  
Reply with quote  
 Post subject: Re: Violet Blue Stone Diamond OR Dud
PostPosted: Sun Dec 05, 2010 9:29 pm 
Offline
Established Member

Joined: Fri Nov 12, 2010 8:56 pm
Posts: 33
JB wrote:
Back to the original post; can someone show me an example of a cabochon cut diamond? Then explain how the cutter dealt with the directional differences of hardness to achieve the cut.

Of course it's not a diamond. Of course the OP needs a professional evaluation.


Hi. Thankyou all, for all your help and advice.
The gem in question has been tested by a professional gemologist refer to page 2.
I am now aware of all the different type of diamond cuts used.
and I apologise for creating confusion.
Thankyou for all the information provided within this site i have found all of the gemology links very helpful. :D
Regards tanias24

Also as soon as i can i will include the images of the inclusions that are in the gem. :)


Top
 Profile  
Reply with quote  
 Post subject: Re: Violet Blue Stone Diamond OR Dud
PostPosted: Mon Dec 06, 2010 9:14 am 
Offline
Gold Member
User avatar

Joined: Thu May 29, 2008 8:32 am
Posts: 1730
Location: Suwanee, GA US
tanias24 wrote:
Thankyou all for your advice and comments.
In regards to the tester in question, all i can tell you is that it was brought from a reputable company, NOT EBAY.
The Supplier specialises in suppliying this equiptment to Professionals in the jewellery trade.
I Will Let You All Know The End Result.
RegardsTanias24

For the record, there are cheap products on eBay, but eBay vs a "reputable" Brick and Mortar does not make any information more reliable. I have done product certification for almost 20 years now in information technology. We even have our terms, the truisms "Vendors Lie" and "Self-Serving Vendor Hype" (SSVH). If it were true that the more expensive, from a reputable dealer were always best, everyone would still have IBM desktop computers. And further proof close to this topic are Bill Hanneman's contributions. Those certainly running at eBay prices compared to some of the other equipment available for various tests. :D

And thanks for everyone finally toning down this thread. It was getting a bit much.

/I just cut

_________________
George Ellis
www.faceting.biz


Top
 Profile  
Reply with quote  
 Post subject: Re: Violet Blue Stone Diamond OR Dud
PostPosted: Tue Dec 07, 2010 4:14 am 
Offline
Valued Contributor

Joined: Tue Oct 19, 2010 3:46 am
Posts: 125
Tanias,
Try not to buy your gemological instruments from ebay,sure bargains can be had but you should be looking for reliable equipment and not mass produced snot from china.For gods sake and your moneyclip get your gem testing equipment from a reliable source untill you know enough about gemtesting equipment and its functions.I had the use of one of these electronic testers recently from an antiques dealer.Results were totally inaccurate too, test showed a beautiful sapphire blue indicolite to be diamond on the tester,if you must use an electronic tester get one that is certified for use by a recognised institute.Even electronics can be inaccurate as previously stated by other posts,electronics DO DEGRADE in time and use as there are many components that make a cicuit,and these components do not all wear evenly,so variation will be inevitable untill the unit simply bites it,where gemology is concerned you owe it to yourself to get the best testing equipment you can afford not what you can get for the least outlay,this of course in general is commensurate with quality obtained.


Top
 Profile  
Reply with quote  
 Post subject: Re: Violet Blue Stone Diamond OR Dud
PostPosted: Tue Dec 07, 2010 6:18 am 
Offline
Established Member

Joined: Fri Nov 12, 2010 8:56 pm
Posts: 33
lightspeed wrote:
Tanias,
Try not to but your gemological instruments from ebay,sure bargains can be had but you should be looking for reliable equipment and not mass produced snot from china.For gods sake and your moneyclip get your gem testing equipment from a reliable source untill you know enough about gemtesting equipment and its functions.I had the use of one of these electronic testers recently from an antiques dealer.Results were totally inaccurate too, test showed a beautiful sapphire blue indicolite to be diamond on the tester,if you must use an electronic tester get one that is certified for use by a recognised institute.Even electronics can be inaccurate as previously stated by other posts,electronics DO DEGRADE in time and use as there are many components that make a cicuit,and these components do not all wear evenly,so variation will be inevitable untill the unit simply bites it,where gemology is concerned you owe it to yourself to get the best testing equipment you can afford not what you can get for the least outlay,this of course in general is commensurate with quality obtained.


Thankyou Lightspeed for your advice :D Just to clarify for one and all i did not buy the item from ebay, the item was brought from an idependent dealer.
Since joining this site i have become aware of the tools of choice, and i am very greatful for the reference guide on this site it is great, And to everyone for their advice and comments. Also I have since taken the gem in question to a gemologist (refer pg2).
Regards tanias :)


Top
 Profile  
Reply with quote  
 Post subject: Re: Violet Blue Stone Diamond OR Dud
PostPosted: Wed Dec 08, 2010 11:19 pm 
Offline
Valued Contributor

Joined: Tue Oct 19, 2010 3:46 am
Posts: 125
No prob Tanias
i have seen these testers going on ebay,i have fallen for equipment on ebay,the results were not good.That being said i did get a microscope off the bay but i would encourage any one contemplating buying there ,for anything ,make sure you get all the questions you have answered and research research research.If the seller isnt willing to answer simple just dont buy.
Welcome to this site by the way,ive had my ups and downs here but there are some really helpful and genuine people that log on here ,the advice and common interest is well worth it,All the best in your gemological pusuits or associated fields .
You are right there is a wealth of info here on this site i'm only new too and am still finding my way around,i unfortunately do come up with some silly questions but its good to be put straight by someone that has knowledge.


Top
 Profile  
Reply with quote  
 Post subject: Re: Violet Blue Stone Diamond OR Dud
PostPosted: Thu Dec 09, 2010 12:13 am 
Offline
Gold Member

Joined: Thu Apr 17, 2008 1:47 am
Posts: 1350
Location: Pacific Northwest
Everything is available on Ebay, good, bad and mediocre. Just because something is purchased on Ebay does not make it suspect but I would be the first to admit that the junk outnumbers the treasures by far.

_________________
I just dreamed that I was a butterfly.


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 50 posts ]  Go to page Previous  1, 2, 3, 4  Next

All times are UTC - 4 hours


Who is online

Users browsing this forum: No registered users and 14 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
Gemology Style ported to phpBB3 by Christian Bullock