Author Topic: Hello all...Large purple red? diamond with blood red flouresence-need to value  (Read 10125 times)

Offline a1co

  • Newbie
  • *
  • Posts: 11
Hello all..
I'm a bit new to this but I have a large red/purple stone tests + on a diamond tester and flouresence is blood red very strong!
it's the size of my little finger nail aprox 10mm round cut in a 18 or 22 ct gold sunburst with hyroglyphic hallmarks both on individual wires of the sunburst and a different hyroglyph on the posts holding the stone...I have been unable to identify the hallmaks exactly but is 100% defininately high ct gold.
excuse any spelling mistakes I'm in the uk..
Would really like to get a picture on here of it flourecing and just to get an idea of value.
All the best, Al

Offline oldmancoyote

  • Member Moderator
  • Hero Member
  • ****
  • Posts: 4367
From your description, it's most likely to be a ruby, but this is a guess, without photos and a lot more information. Take it to a jeweller or a gemmologist - they should be able to identify it for sure and also tell you if it is synthetic or natural.

As to value, it's really impossible to say without positive identification and viewing the stone - too much depends on factors such as colour, clarity, size and cut that need to be assessed with the stone in hand.
« Last Edit: December 09, 2011, 02:29:31 PM by oldmancoyote »

Offline a1co

  • Newbie
  • *
  • Posts: 11
Thankyou for advice.
Would a ruby test positive on an electronic tester? and do Ruby's fluoresce like that ? IE real color charge?
it appears more purple than red in ordinary light but comes alive in sunlight
there are no scratches or marks at all on the surface of it and the brooch that its in is obviously very old so dint think its a lab grown one.
Thanks again,,
 this has been intriguing me for nearly 2 years now so its time to work it out.

Offline oldmancoyote

  • Member Moderator
  • Hero Member
  • ****
  • Posts: 4367
Electronic tester: in a setting any reading on thermal conductivity will be misleading, and that's what most testers rely on.

The bright red fluorescence is precisely what makes me think it is a ruby - red fluoro is extremely rare in diamonds (and unknown at the LW UV wavelength typical of most consumer UV lamps).

As to scratches or marks - ruby is definitely very hard, and unless it's been kept very badly it's not a surprise if it has no scratches even on an old piece.

Finally, I have no idea if it is synthetic or not, but bear in mind that the first synthetic rubies were produced before 1850 and sold on a commercial scale in the very early 1900s...

Here's a good photo of what typical ruby LW UV fluoro looks like (ignore the upper part of the stone, which has been flux healed - look at the bottom half):

« Last Edit: December 09, 2011, 02:59:06 PM by oldmancoyote »

Offline Diamondsbylauren

  • Administrator
  • Hero Member
  • *****
  • Posts: 9078
    • Diamonds By Lauren
Red fluorescence?

I don't recall ever seeing that......in a diamond
Interesting stuff OMC!!!

Welcome a1co!!!
« Last Edit: December 09, 2011, 03:03:14 PM by Diamondsbylauren »
David
Check out our YouTube Channel

Offline dovesgate

  • Hero Member
  • *****
  • Posts: 729
A ruby has a hardness of 9 and a diamond of 10 so I know on some electronic testers a ruby will look like it tests as a diamond. I have made a friend in the pawn business so she let's me play with her equipment once in a while.

I bought a ring with a synthetic ruby that didn't brighten in color in sunlight. When I found out it was manmade I switched it out with a natural. It's normal color ranges from deep red to a bright fuschia when it is in sunlight. I read somewhere that that's what is supposed to do, brighten in UV light.

Offline oldmancoyote

  • Member Moderator
  • Hero Member
  • ****
  • Posts: 4367
Red fluorescence?

I don't recall ever seeing that......in a diamond
[snip]

I'm sure you have - or at least you have seen one diamond that does ;)

The Hope is red under SW (<250 nm), and it has red phosphorescence too.

Under "normal" LW UV (>300 nm), red is unknown - at least in the texts I have.

Offline a1co

  • Newbie
  • *
  • Posts: 11
OK.. well have to admit I know nothing..and am on a learning curve ..
Thank you all...
 I will absorb and digest all information I'm given here as you are  the first sensable knowledable collective I have found.
I do have other diamonds (and tested my girlfriends engagement ring 1/4 ct clear set in a ring) and it  seemed to have the same reaction on the electronic tester. even the 0.25 chips on another ring?
will have to try it on a ruby.
and it is more light purple than red after again looking at it under a compact fluorescent 11 watt bulb (normal not UV)
fluoresced under a 2' black light UV tube does not under a blue UV bill checker or UV nail  dryer.
It is a round classic diamond cut in a wire sunburst mount.
Thankyou all again...Alex

Offline oldmancoyote

  • Member Moderator
  • Hero Member
  • ****
  • Posts: 4367
Corundum (ruby and sapphire) has a relatively high thermal conductivity. Depending on stone size, room temperature and your tester's precision/sensitivity a false reading is highly possible, and testing set stones is not advisable in any case. This is particularly the case if your tester is of the yes/no variety, rather than the type that gives you a reading of the measured thermal conductivity.

If I were to bet at this stage, I think you have a synthetic corundum - whether one calls it ruby or purple sapphire is rather irrelevant. Rings in a simple setting with a large synthetic stone were very popular in the first quarter of the 1900s, with lovely looking stones: nice bright colour, and almost no inclusions even using a loupe.

Offline a1co

  • Newbie
  • *
  • Posts: 11
etc..
« Reply #9 on: December 10, 2011, 08:47:47 AM »
The tester is a diamond selector 2 with a led scale,  and audible bleeps...
Have taken some pictures and will try to upload them later. Its the Arabic/hieroglyphic type hallmarks that intrigue me as there is 1 on each of the posts supporting the stone and would probably tell me what the stone is if I could understand them.
Thanks again everyone, most appreciated.

Offline Debangel

  • Sr. Member
  • ****
  • Posts: 305
Re: etc..
« Reply #10 on: December 10, 2011, 10:30:53 AM »
The tester is a diamond selector 2 with a led scale,  and audible bleeps...
Have taken some pictures and will try to upload them later. Its the Arabic/hieroglyphic type hallmarks that intrigue me as there is 1 on each of the posts supporting the stone and would probably tell me what the stone is if I could understand them.
Thanks again everyone, most appreciated.

I don't claim to be terribly informed on the topic, but could the markings simply indicate the Egyptian Revival (I think that's what it was called...OMC to the rescue?) period in jewelry? When Tut's tomb was opened, and everything Pharaoh was all the rage?

Offline oldmancoyote

  • Member Moderator
  • Hero Member
  • ****
  • Posts: 4367
OMC to the rescue - yes, it was Egyptian Revival. But there were at least 3 in jewellery: one in the early 1800s following Napoleon's campaigns in Egypt; the second one around the end of the 1800s following nothing in particular other than a fashion for "antique" style jewellery, and the third one in the 1920s with the discovery of King Tut's tomb etc. etc.

Alex - if you post pictures, by far the easiest and highest quality way of doing that is through a web hosting service, be it Facebook or one of the dedicated photo hosts (Photobucket, Picasa, ImageShack, etc.). Send me an email if you have technical problems; at this point I'm rather intrigued. My email is available by clicking on my username next to any of my posts.

Offline clgwli

  • Administrator
  • Hero Member
  • *****
  • Posts: 4491
I admit I am very interested to see photos as well.  I had a ruby that was very similar sounding in color and the fluor of the stone.  I love seeing old pieces of jewelry no matter what :)
Elaine aka Squiggly
elaine@diamondsbylauren.com

Offline Trinkette

  • Hero Member
  • *****
  • Posts: 7796
Natural red spinel sourced from Burma can fluoresce strong red.



Offline a1co

  • Newbie
  • *
  • Posts: 11
pictures....
« Reply #16 on: December 10, 2011, 02:33:57 PM »
http://s1122.photobucket.com/albums/l534/a1co/?action=view&current=DSCF2734.jpg

well not sure if i've done this right but here are some links...

Offline a1co

  • Newbie
  • *
  • Posts: 11
http://s1122.photobucket.com/albums/l534/a1co/?action=view&current=dia1.jpg

I will take some better pictures with my friends camera tomorrow as I would like you all to see the hallmarks up close as I'd love to know exactly what they mean...Thanx in advance everyone for helping me. Alex


Offline oldmancoyote

  • Member Moderator
  • Hero Member
  • ****
  • Posts: 4367
Hey Alex- good photos. The link you want to copy is the bottom one in photobucket - the one that reads "IMG Code".

Here's those I can find:








Based on these - I'd be very surprised if it is a diamond. The colour, the refraction and the slight wear at the edges of the table point to something different. Could be a corundum, a spinel (natural or synthetic) or an alexandrite (also natural or synthetic) - does it change colour at all when going from artificial to natural light?

The third photo suggests spinel, since I cannot see any birefringence (doubling of facet edges), and spinel is the only one of the three that is singly refringent. But to go further on this requires having the stone.

You mentioned the UK - are you anywhere near London? I can suggest a couple of people there to help you with ID.

Offline a1co

  • Newbie
  • *
  • Posts: 11
Thanx
« Reply #20 on: December 10, 2011, 03:38:28 PM »
Well thankyou for all your advice, it only ocoured to me after seeing how detailed the pictures would be thatI should have cleaned it looking through a loup its very dirty...will try again with better camera!
cheers everyone...

Offline dovesgate

  • Hero Member
  • *****
  • Posts: 729
It reminds me of the synthetic alexandrite I used to have.

Offline a1co

  • Newbie
  • *
  • Posts: 11
and would alexandrite test possative on the tester tho?

Offline oldmancoyote

  • Member Moderator
  • Hero Member
  • ****
  • Posts: 4367
You are relying way too much on the tester. You are testing the stone in the incorrect environment (in a setting), and have no idea whether the tester is even calibrated correctly. That it tests positive on a few diamonds is no proof of correct calibration, considering that those testers are produced to help in the ID of diamond simulants such as paste and CZ, not of other gemstones that look nothing like diamonds and are generally pretty good heat conductors.

I can pretty much assure you that the stone is not a diamond - as I have already done above. It simply does not look like one, and that colouring in diamonds is unknown, as is red fluorescence at LW UV.
« Last Edit: December 10, 2011, 05:07:48 PM by oldmancoyote »

Offline Trinkette

  • Hero Member
  • *****
  • Posts: 7796
Knowing the RI would help a lot here. For now, I am sticking by spinel.