Mystery stone - guesses please

[beaujolais]

ieatbugs

Two threads above this. Cute user name, for sure.

Back to the regularly scheduled programming . . .

 

[Quantz Studios]

LD, there's no question about this being an opal. I'm not convinced it's treated, but it's something I want to determine since precious opal with a transparent natural blue body color is quite uncommon. Uncommon enough that the difference in value between untreated and treated is rather large. You know... I just want to be sure it's not dyed or anything before I declare it something it might not be.

My pictures are no secret, lol. I use an Olympus SP-800UZ which can be a real pain in the butt with certain shots and lighting. I just use a neutral background, usually grey, and daylight-equivalent lighting. Nothing fancy at all... Simple editing like adjusting brightness and white balance to get the pictures to look on the monitor as close to how I see things with my own eyes.

 

[ieatbugs]

ieatbugs

Two threads above this. Cute user name, for sure.

Back to the regularly scheduled programming . . .

Thanks! It was a habit I had as a child that mortified my parents, but I decided to embrace as an adult.... ;D

 

[davi_el_mejor]

Curious!

What happens to the body color when you soak it in water?

 

[LD]

LD, there's no question about this being an opal. I'm not convinced it's treated, but it's something I want to determine since precious opal with a transparent natural blue body color is quite uncommon. Uncommon enough that the difference in value between untreated and treated is rather large. You know... I just want to be sure it's not dyed or anything before I declare it something it might not be.

My pictures are no secret, lol. I use an Olympus SP-800UZ which can be a real pain in the butt with certain shots and lighting. I just use a neutral background, usually grey, and daylight-equivalent lighting. Nothing fancy at all... Simple editing like adjusting brightness and white balance to get the pictures to look on the monitor as close to how I see things with my own eyes.

Stonebender - Lightning Ridge Opal typically comes in blue (see one of mine below - not a great stone but a good photo to show the blue). This was actually sold as "semi black" and quite a lot with a blue body colour are sold in this way. I'm also attaching a photo of another one of my "semi black" opals. I think it looks remarkably like the stone you're investigating. The main difference is the one you have is faceted and they're less common than cabs.

I'm not convinced about the difference in value being large though? If this were dyed I doubt it would perform as the photos suggest. Opals with this body colour are not particularly expensive. The only reason I bought the loose stone was because it showed purple and that's less common than blue/green etc.

 

[beaujolais]

Thanks for the camera/photo info, Ryan.

When I soaked it in water, the translucent window area became clear. Within a day or two after being out of water, it became translucent again.

---

Now, Ieatbugs:

It was a habit I had as a child that mortified my parents, but I decided to embrace as an adult.... ;D

So, you have embraced it by still eating bugs? OK, to each his own.

Now, back . . .

 

[Quantz Studios]

Soaking in any liquid didn't do much to the stone- nothing like I've seen usually in Ethiopian/hydrophane opals. This stone is already very translucent! It sucked up some and the translucency went completely water-clear like some opals do, but it didnt haze up or get opaque and dull like other opals i've seen. It's normal appearance returned within a matter of hours. This conflicts a bit with Sonoma's experiments, but I AM in the desert- things dry out faster here.

LD, I'm sorry but I have to oppose you here. Aside from the play of color, this stone has a true body color that is blue and shifts greatly towards red in different lighting. Other "blue" opals appear blue because of the play of color, even the adularescence in translucent/transparent opal creates a milky blue color in the stone if the body is light enough to show it. I have quite a few examples of these kind of stones. The two stones you show I am almost certain are not blue in body color- that is the color-play that is creating the blue. Those look like what you said- Semi-black opals, with a predominantly blue color play. I'll bet those stones are nearly opaque, translucent at best and in transmitted light will likely be a grey color with a little bit of yellow haziness. The value difference would be high, in my opinion, and I dont think this stone is in the same category as a LR semi-black stone. Besides the lighter grey-blue stones out of NV and OR which aren't really similar... Those are even very rare, I've never seen one like this and in my research they are very uncommon. I have seen dyed ones that are bright purples and blues- unnaturally bright! I've seen them for sale too, cheap. But i've never seen one with this sort of coloring.

 

[ieatbugs]

It's hard to compare the opals that are cabochons to the faceted cut of the mystery stone, too.

 

[minousbijoux]

Wow, Sonoma, you had no idea what you were starting with this thread, huh?!!

 

[Quantz Studios]

It's hard to compare the opals that are cabochons to the faceted cut of the mystery stone, too.

It's not that difficult. You just have to ignore the cut/shape and concentrate on the inherent qualities of the stones themselves.

 

[ieatbugs]

It's hard to compare the opals that are cabochons to the faceted cut of the mystery stone, too.

It's not that difficult. You just have to ignore the cut/shape and concentrate on the inherent qualities of the stones themselves.

I'm sure it's not difficult for you, but just looking at photos, it's not the easiest!

 

[Quantz Studios]

I thought you mean just "in general", my fault! Yeah, from pictures if you aren't very familiar with the materials I can see how it can be difficult. If they're in front of you, it's not too difficult at all.

 

[Lovinggems]

Looks like Australian black opal.

 

[LD]

Stonebender - I'm not disagreeing for the sake of it but the ring I showed has a blue body colour, not play. It actually doesn't look grey at all and remains blue in all lights. Where it is deficient is in the play of colour. It has lighter blue and some other flashes but nothing spectacular. I bought it because of the body colour. I have a fairly large collection of opals so do understand the difference.

What I think we definitely agree on is that the mystery stone isn't a hydrophane. I'm glad that it's a natural rather than synthetic because it's an interesting gem.

 

[Quantz Studios]

I guess we'll have to agree to disagree on that, then.