This qualifies as hand-made jewelry, I watched John take a 18kt gold wire & build this framework around this opal. The stone is over 14cts & is gently held in place with the prongs, work took about 2.5hrs & I think it shows very well-stevie...
I think we all did, it just wasn't an argument worth having when it's such a nice stone anyway. Style of cutting is almost as good an indicator as anything else in most cases (not that one should rely on that of course).
Joined: Fri Feb 24, 2006 1:20 am Posts: 2756 Location: Southern California, U.S.A.
Stephen Challener wrote:
I think we all did, it just wasn't an argument worth having when it's such a nice stone anyway. Style of cutting is almost as good an indicator as anything else in most cases (not that one should rely on that of course).
Well, there's the matter of value. LR produces some extremely fine non-dark "crystal" opal that's valued for its excellent stablity and it isn't hydrophane. It sells at significantly higher prices than its Ethiopian counterpart and carries the LR cachet. I questioned LR origin the instant I saw the images.
Lightning Ridge opal cert. by Frank Schaffer. resized copy.jpg [ 60.83 KiB | Viewed 3514 times ]
Attachment:
Australian opal appr, Paul 2012. - Copy resized.jpg [ 77.55 KiB | Viewed 3514 times ]
I get this comment a lot because the opal does show like ethiopean opal at a glance, this stone was bought by F Schaffer, one of 2 or 3 stones he bought at the same time from the mine owner in Australia. He bought the stones, the smaller one cut/polished to over 14 cts, the larger one over 24 cts. & recently sold for about the same price per ct., a little more maybe, within the last year. Im posting 2 papers, a cert from Frank for origin because he bought the stone & knows where it came from, & an appraisal done years ago by Paul who is familiar with opal & locations of said stones, he knows the difference & can make a proper decision with his scope & other tools at his disposal plus he always references his findings with other people he works with. Im satisfied with the results, other appraisers do agree with the findings I present to them. I had a similar issue with the Paraiba tourmaline I have & I finally sent it to GIA for ID, it came back as Brazilian paraiba from the original mine, 1 of 3 in the area, so I can live with the info on the opal as sound-
Joined: Fri Feb 24, 2006 1:20 am Posts: 2756 Location: Southern California, U.S.A.
Ruby, there's a simple "at-home" test that can pretty much resolve the question. Moisten the tip of your finger and touch it to the opal. If the stone wants to cling to your finger it's hydrophane (likely Ethiopian). If it doesn't it's probably from another source. Mexican precious opal can also be hydrophane, as is some from U.S. sources.
A lot of ethiopian hydrophane opal wont "cling", but will still soak up water and is therefore hydrophane. A non sticky feeling opal may still be of ethiopian origin even if it doesnt have that hydrophane "feeling".
_________________ Professional Gemologist and Microscopist
The views expressed here are the author's opinions and do not necessarily reflect those of the his employer.
Users browsing this forum: No registered users and 3 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